The American Journal of Tropical Medicine and Hygiene - Volume 73, Issue 4, 2005

Leptospirosis is a global zoonotic disease with a variety of clinical manifestations. We report an outbreak of leptospirosis in the Yaeyama Islands, Japan, in the summer of 1999 associated with heavy rainfall. Fourteen people were diagnosed with leptospirosis and required hospitalization. All cases were found to have exposure to contaminated soil or water. A history of recreational activities involving water sports was more frequent (71%) than occupational risk factors related to agriculture or construction (29%). Fever was the primary symptom in all cases, followed by chills (93%), headache (86%), myalgias (57%) and conjunctival suffusion (57%). All cases were successfully treated with antimicrobial therapy except one patient who improved spontaneously. Jarisch-Herxheimer reactions were seen in six cases (43%). The increasing incidence of leptospirosis related to recreational sports is an important public health problem in resort areas. A high-index of suspicion, early treatment, and prevention are crucial in this latently endemic area.

Pneumonia is a common manifestation of melioidosis, the disease caused by Burkholderia pseudomallei. In this study, we defined the prognostic significance of a positive sputum culture. A total of 712 patients presenting to Sappasithiprasong Hospital, Ubon Ratchathani, Thailand, with melioidosis between January 1992 and December 2002 had a sputum culture performed during admission, which was positive for B. pseudomallei in 444 patients (62%). The median duration of sputum positivity was 9 days (range, 1 to 49 days). Sputum cultures were negative in 32% of patients with radiologic changes suggestive of pulmonary involvement. Overall in-hospital mortality was 48%. A positive sputum culture was associated with mortality (adjusted OR 2.8, 95% CI: 1.9, 4.0; P < 0.001). This was independent of renal disease, a prior history of melioidosis, positive blood cultures, and other potential confounders. The presence of B. pseudomallei in the sputum of patients with melioidosis is associated with a poorer prognosis.

Rickettsia felis is maintained transovarially in Ctenocephalides felis fleas in a widespread geographic distribution and is transmitted to humans and animals, including opossums. This rickettsia is phylogenetically a member of the spotted fever group, most closely related to Rickettsia akari and R. australis. An unusual feature of this rickettsia is that the gene for the outer membrane protein A (OmpA) is interrupted by stop codons. To determine if this putatively dying gene is expressed, mRNA was extracted from laboratory-maintained, R. felis–infected cat fleas. Reverse transcriptase–polymerase chain reaction amplification of three segments of the ompA gene indicated that mRNA of ompA is actively transcribed in fleas. The cDNA sequences expressed represented mRNA of the first 1860-basepair segment of ompA, which includes domains I and II, part of domain III, the region from site 1836 to site 2180, despite the presence of several stop codons, and the open reading frame from site 2788 to site 3837. The detected sequences showed several differences in the amino acid composition when compared with the previously reported sequence.

Scrub typhus is one kind of rickettsial disease and may cause fever, cough, and skin rashes in infected humans. Regarding liver involvement, it was uncommon to be reported in previous medical literature from Western countries. This study observes the relationship between scrub typhus and liver function. From January 1998 to August 2003 in Kaohsiung Chang Gung Memorial Hospital in Taiwan, we observed 30 patients with scrub typhus, and 29 of them had liver function abnormality. In these patients, we found 89.3% with elevated aspartate aminotransferase (AST) levels, 91.7% with elevated alanine aminotransferase (ALT) levels, 84.2% with elevated alkaline phosphatase (ALP) levels, and 38.5% with elevated total bilirubin levels. In our study, there is a close relationship between scrub typhus and impaired liver function tests. Therefore, if patients are found with fever of unknown origin and abnormal liver function, we should take scrub typhus into consideration.

This report summarizes the status of the Dracunculiasis Eradication Program as of early 2005. Nine of the 20 countries that were endemic for this disease when the program began have already interrupted transmission, Asia is free of Guinea worm, and five of the remaining disease-endemic countries reported less than 50 cases each in 2004. Ghana and Sudan each reported 45% of the 16,026 cases in 2004. Except for Sudan, whose reports are delayed, cases in the remaining disease-endemic countries were reduced by 61% during the first quarter of 2005 compared with the same period of 2004. With accelerating momentum towards zero cases in all countries, the recent settlement of Sudan’s north-south civil war, and a new challenge grant from the Bill & Melinda Gates Foundation, the way now seems clear to finish eradicating dracunculiasis by 2009 in Sudan and earlier elsewhere.

“The rule of the final inch . . . The work has been almost completed, the goal almost attained . . . In that moment of fatigue and self-satisfaction it is especially tempting to leave the work without having attained the apex of quality . . . In fact, the rule of the Final Inch consists in this: not to shirk this crucial work. Not to postpone it . . . And not to mind the time spent on it, knowing that one’s purpose lies . . . in the attainment of perfection.”

—Alexander Solzhenitzyn, The First Circle

Although maize pollen is known to provide nutrition for larval anopheline mosquitoes, the epidemiologic relationship between maize agriculture and malaria transmission has never been defined. To determine whether recent changes in malaria transmission in Ethiopia might be linked to the spread of maize as a commercial crop, we compared malaria transmission and maize cultivation intensity in 21 villages in the Bure District of northwestern Ethiopia where maize cultivation has recently expanded. The cumulative incidence in high maize cultivation areas was 9.5 times higher than in areas with less maize. A chi-square goodness-of-fit test results showed that malaria cases were not distributed evenly among categories of maize cultivation intensity, (χ2 = 1,578, P < 0.001). A Poisson regression suggested that the intensity of maize cultivation, controlled for differences in elevation between sites, was positively and significantly correlated with malaria incidence. Thus, the intensity of maize cultivation was associated with exacerbated human risk of malaria in Bure.

The efficacy of sulfadoxine-pyrimethamine (SP) and amodiaquine (AQ) was assessed at Kivunge and Micheweni in Zanzibar, Tanzania, in 2001. The main objective was to obtain baseline data after observations of high levels of chloroquine treatment failures. Children (6–59 months) were randomized to receive either drug. At Kivunge, SP and AQ were given to 64 and 63 cases, while for Micheweni, 61 and 70 cases were treated. Main findings were overall high rates (> 90%) of adequate clinical response (ACR) with AQ. A lower ACR was seen in the SP group at Kivunge (87.1%) compared with Micheweni (94.8%). Furthermore, in the ACR group, 16.7% AQ parasitological resistance (RI–RIII) was encountered at Kivunge. Most of the cases of SP parasitological resistance (14.5%; RI/RII) were seen at Micheweni. Notwithstanding this, the overall treatment failure was only 9.2% with SP and 5.5% with AQ. The Zanzibar Ministry of Health has since reviewed its antimalarial drug policy.

A vaccine trial was conducted to determine the efficacy of a multicomponent candidate vaccine, FALVAC-1, against Plasmodium falciparum in Aotus nancymai monkeys. After two immunizations, animals were challenged intravenously with parasites of the Vietnam Oak Knoll (FVO) strain of P. falciparum. The primary outcome was to determine the protective response of the monkeys to immunization with the FALVAC-1 antigen produced in baculovirus when combined with different adjuvants (alum, QS-21, ASO2a, CRL1005/oil, and CRL1005/saline) as compared with FALVAC-1 with FCA/FIA and antigen alone. When compared with the monkeys immunized with FALVAC-1 alone, FALVAC-1 with FCA/FIA reduced the mean parasite count (to Day 11), reduced the mean accumulated parasitemia (through Day 11), and extended the number of days to treatment. None of the other 5 antigen-adjuvant combinations were able to provide discernable levels of protection based on log(parasitemia) and log(cumulative parasitemia) to Day 11.

Malaria infection during pregnancy increases the risk of adverse birth outcomes among HIV-infected women. The role of umbilical cord parasitemia is not well characterized. We examined the risk of adverse perinatal outcomes in relation to maternal or umbilical cord Plasmodium falciparum parasitemia among 275 HIV-infected women from Tanzania, who participated in a randomized trial of zinc supplementation during pregnancy. Maternal parasitemia (≥1/μL) at the first antenatal visit was associated with increased risk of low birth weight < 2,500 g (adjusted relative risk [ARR] = 2.66; P = 0.01) and preterm delivery < 37 weeks (ARR = 1.87; P = 0.06). Maternal parasitemia at delivery was associated with preterm delivery (ARR = 2.27; P = 0.008), intrauterine growth retardation (ARR = 1.92; P = 0.03), and neonatal death (ARR = 3.22; P = 0.07). Cord parasitemia was associated with a large and significant increase in the risk of neonatal death (ARR = 8.75; P = 0.003). Maternal parasitemia at the first antenatal visit was strongly related to parasitemia at delivery, and the latter was associated with cord blood parasitemia. CD4 cell counts, parity, or assignment to the zinc arm (25 mg daily) were not associated with parasitemia in maternal or cord blood at delivery. Successful treatment of HIV-infected women who present to the first prenatal visit with malaria parasitemia and avoidance of reinfection are likely to decrease the risk of adverse outcomes during pregnancy and the early postpartum period. Cord blood parasitemia is a strong predictor of neonatal death. The potential effect of zinc supplementation on clinical malaria outcomes deserves future investigation.

Protein-energy malnutrition (PEM) affects millions of children in the developing world. The relationship between malaria and PEM is controversial. The goal of this study was to evaluate whether undernutrition is associated with increased or decreased malaria attributable morbidity. Three cross-sectional surveys were conducted using insecticide-treated bed nets (ITNs) among children aged 0–36 months living in an area with intense malaria transmission. Data were collected on nutritional status, recent history of clinical illness, socioeconomic status, current malaria infection status, and hemoglobin. In multivariate models, stunted children had more malaria parasitemia (odds ratio [OR] 1.98, P < 0.0001), high-density parasitemia (OR 1.84; P < 0.0001), clinical malaria (OR 1.77; P < 0.06), and severe malarial anemia (OR 2.65; P < 0.0001) than nonstunted children. The association was evident in children with mild-to-moderate (−3 < height-for-age Z-score [HAZ] < −2) and severe stunting (HAZ < −3). The cross-sectional nature of the study limits the interpretation of causality, but the data provide further observational support that the presence of undernutrition, in particular chronic undernutrition, places children at higher, not lower risk of malaria-related morbidity.

Despite different recommendations from WHO and national authorities, artesunate monotherapy is increasingly used for treating African children with malaria. A 5-day course of oral artesunate (first day: 4 mg/kg body weight, observed intake; and 2 mg/kg body weight on the following days with nonobserved drug intake) yielded a PCR-corrected Day 28 cure rate of 90% (45 of 50 patients; CI 78–97%) in Gabonese children aged between 2 and 18 months. Artesunate was well tolerated, and no severe adverse events were reported.

Lactoferrin (LF) is an important biologic molecule with many functions, one of which is antimicrobial defense. We evaluated the growth-inhibiting effects of four types of LF (native LF, Fe+3-bound [holo] LF, Fe+3-free [apo] LF, and LF hydrolyzate) on the in vitro growth of Babesia caballi and B. equi. The growth of B. caballi was significantly suppressed in media containing apo LF, but was not inhibited in media containing native LF, holo LF, or LF hydrolyzate. The growth of B. equi was not inhibited by media containing native LF, holo LF, or apo LF. These data indicate that apo LF had the strongest inhibitory effect on B. caballi. This may have been caused by inactivation or inhibition of a growth factor in the culture medium.

Historically, non-combat injuries and illnesses have had a significant impact on military missions. We conducted an anonymous cross-sectional survey to assess the prevalence and impact of common ailments among U.S. military personnel deployed to Iraq or Afghanistan during 2003–2004. Among 15,459 persons surveyed, diarrhea (76.8% in Iraq and 54.4% in Afghanistan), respiratory illness (69.1%), non-combat injuries (34.7%), and leishmaniasis (2.1%) were commonly reported. For all causes, 25.2% reported that they required intravenous fluids, 10.4% required hospitalization, and 5.2% required medical evacuation. Among ground units, 12.7% reported that they missed a patrol because of illness, and among air units, 11.7% were grounded because of illness. The incidence of diarrhea and respiratory infections doubled from the pre-combat to combat phases, and the perceived adverse impact of these illnesses on the unit increased significantly during the combat phase. Despite technologic advances in warfare and preventive medicine, illness and non-combat injuries have been common during operations in Iraq and Afghanistan, resulting in frequent transient decreases in operational efficiency.

We conducted a cross-sectional study to determine the incidence of visceral leishmaniasis (VL) and risk factors in two villages in Uttar Pradesh, India reported to have had a recent outbreak. In 245 households with 2,203 people, we detected 3 current VL cases, 32 past cases, and 8 VL deaths since 2001 (annual incidence = 6 per 1,000). Risk factors included living in the same household as a VL case (odds ratio [OR] = 76, P < 0.0005 in one village and OR = 22, P < 0.0005 in the other village), sleeping downstairs and outside in the summer (OR = 4.7, P = 0.004), and an age ≥ 15 years old (OR = 2.9, P = 0.024). Increasing cattle density was a risk factor in one village but not the other. We were not able to determine the route by which VL entered the villages. Our data demonstrate a new spread of VL in previously unaffected areas. We recommend carefully supervised spraying with DDT, surveillance to pinpoint other affected villages, and efforts to increase availability of diagnostic and treatment facilities.

The population genetic structure of the African malaria vector Anopheles arabiensis from western Kenya, the Great Rift Valley, and coastal Kenya was investigated using 12 microsatellite loci and a partial sequence of mtDNA dehydrogenase gene subunit 5 (ND5). The mean number of alleles and the observed heterozygosity were similar for the mosquito populations from the three regions as revealed by the microsatellite data. A total of 30 polymorphic sites in the ND5 gene defined 39 haplotypes. Six haplotypes were shared among four populations from the three distinct ecological conditions, and they constituted 92% of the total number of individuals sequenced. Mitochondrial haplotype and nucleotide diversity were high. Microsatellite markers within polymorphic inversions revealed a level of genetic differentiation (FST = 0.116) four to seven times higher than markers outside inversions (FST = 0.016) or inside fixed inversions (FST = 0.027). Mitochondrial ND5 gene sequences did not reveal significant genetic differentiation for the same four populations (ΦST = −0.008). The contrasts in the level of genetic differentiation between microsatellite markers inside polymorphic inversions, the mitochondrial ND5 gene, and microsatellite markers outside inversions suggest that the level of genetic differentiation in An. arabiensis populations across the Great Rift Valley varies significantly among different areas of the genome. Variations in the degree of genetic differentiation with respect to the chromosomal location of microsatellite markers may result from intrinsic characteristics of the markers, demographic or historic factors affecting these populations, and the possible adaptive significance of chromosomal inversions to climatic conditions.

Lutzomyia longipalpis, a sibling complex, is the main vector of Leishmania chagasi/infantum. Discriminating between siblings is important as they may differ in vectorial capacity. Lutzomyia longipalpis populations display distinct male sex pheromone chemotypes. We investigated the phylogeographic pattern of variation at microsatellite loci from 11 populations from Brazil and Venezuela related to their male pheromone. Temporal genetic differentiation was mostly not significant at the same site. Spatial genetic differentiation was, however, strong, although there was only a weak relationship between genetic differentiation and the geographic distance separating the samples (r 2 < 0.10); geographic separation explained a much greater (54–97%) percentage of the genetic differences among populations when samples with the same pheromone type were analyzed separately. A cluster analysis showed five groups: Lu. cruzi (Brazil) and Lu. pseudolongipalpis (Venezuela) as separate species, two (mostly 9-methyl-germacrene-B) Venezuelan and Brazilian groups, and a very distinct cluster of Brazilian cembrene populations.

First identified in three North American states in 1998, Aedes japonicus japonicus, the Asian bush mosquito, has since spread to 21 states, plus Ontario in Canada, northern France, and Belgium. Analyses of the introduction and expansion of this potentially deadly disease vector will be radically improved by including powerful genetic markers like microsatellites. Useful microsatellite loci have, however, been difficult to identify for mosquitoes in the genus Aedes because of the high amount of repetitive DNA in these species. We isolated single-copy DNA from Ae. j. japonicus and then used a standard enrichment method to identify regions containing microsatellites. Here we describe seven polymorphic microsatellite loci that were tested in American populations of Ae. j. japonicus. These loci were also found to be polymorphic in two other of the four Ae. japonicus subspecies and in Aedes koreicus.

Malaria kills more than one million people a year, and understanding the historical association between its most notorious causative agent, Plasmodium falciparum, and its mosquito vectors is important in fighting the disease. We present a phylogenetic analysis of a number of species within the mosquito subgenus Cellia based on a selection of mitochondrial and nuclear genes. Although some of these relationships have been estimated in other studies, generally few species were included and/or statistical support at many nodes was low. Here we include two additional species of anthropophilic P. falciparum malaria vectors and reanalyze these relationships using a Bayesian method that allows us to simultaneously incorporate different models of evolution. We report data that indicate a paraphyletic relationship between five anthropophilic African mosquito vectors. Such a relationship suggests that these species can serve as independent natural experiments for anopheline immunologic responses to regular, prolonged contact with P. falciparum.

This report presents the results of the Vanuatu mid-term evaluation of the lymphatic filariasis elimination program being implemented countrywide. Vanuatu is one of the first countries to initiate this program as part of the Global Program for Elimination of Lymphatic Filariasis, based on a five-year annual mass drug administration (MDA) of albendazole and diethylcarbamazine and complemented in Vanuatu by extensive coverage with bed nets. This paper reports results of 561 persons tested at eight sentinel sites following two years of MDA. Coverage was 72% and bed net use was more than 70%. Antigen prevalence was reduced by 63% (from 22% to 8%) and prevalence of microfilaremia prevalence was reduced by 93% (from 12% to 0.8%). Results of surveys of health workers and the community are also reported, and the methodology used for this evaluation is discussed.

To assess clinical findings associated with Wuchereria bancrofti infection, 192 school children in a filariasis-endemic area of Haiti underwent physical and ultrasonographic examinations and testing for circulating filarial antigen (CFA). The CFA-positive children were more likely than CFA-negative children to have severe interdigital lesions (≥1 macerated lesion with involvement of ≥4 toe web spaces) (P < 0.0001) and inguinal (P = 0.003) or crural (P = 0.004) lymph node pathology. In multivariate analysis, CFA positivity remained a significant predictor for severe interdigital lesions (P = 0.006) and inguinal lymph node pathology (P = 0.05). Ultrasound detected adult worms and lymphangectasia (diameter = 2.0–4.0 mm) in 11 (10.8%) CFA-positive children. Among CFA-positive children, ultrasonographic detection of adult worms was associated with inguinal (P = 0.01) and crural (P = 0.004) lymph node pathology and advanced pubertal stage (sexual maturity rating = 3–5) (P = 0.02). This is the first study to associate interdigital lesions with filarial infection in children.

We identified 114 patients with neurocysticercosis admitted to Ben Taub General Hospital in Houston, Texas between January 1994 and June 1997. Most of these patients were born in Mexico (78%) or Central America (16%), but 6% were born in the United States. Review of neurology clinic records identified 54 patients diagnosed with neurocysticercosis, representing 2% of all neurology clinic patients and 16% of all Hispanics diagnosed with seizures. Forty-one patients were interviewed and all reported significant risk factors for infection, including ingestion of undercooked pork, pig husbandry, immigration from and frequent travel to villages in disease-endemic areas, or personal/ family history of taeniasis. Among Mexican immigrants, most were born in rural areas in Central (31%) or north central Mexico (38%). Significantly fewer of the patients were from the border states (15%). The median period from immigration to diagnosis was 58 months, but it was 28 months for the 13 patients who had not left the United States after immigration. Although neurocysticercosis is being diagnosed with increasing frequency in the United States, acquisition of infection is still strongly associated with pig husbandry in rural Latin America, with little evidence of local transmission. Even among urban immigrants to the United States and United States–born cases, there is close ongoing contact with disease-endemic villages.

The assay of choice for serological detection of cysticercosis in humans and pigs is the enzyme-linked immunoelectrotransfer blot (EITB), a Western blot assay that relies on the use of seven lentil-lectin–purified glycoproteins (LLGPs) derived from Taenia solium metacestodes. The EITB is has a sensitivity of 98% and a specificity of 100% in detecting cysticercosis, yet scarcity of native source material and the labor-intensive process of metacestode purification hinder its practicality. These limitations have necessitated the reproduction of the EITB antigens in synthetic forms. Four chemically synthesized LLGP antigens, TS14, TS18var1, TSRS1, and TSRS2var1, were assayed individually by enzyme-linked immunosorbent assay (ELISA) and Western blot for immunoreactivity against a large cohort of sera from clinically defined neurocysticercosis patients. The sensitivity and specificity of all four of these antigens using the ELISA format were well below the standards set by the LLGP EITB, whereas results of the Western blot format closely mirrored those of the LLGP EITB.

Sub-Saharan Africa is disproportionately burdened by intestinal helminth and human immunodeficiency virus (HIV)-1 infection. Recent evidence suggests detrimental immunologic effects from concomitant infection with the two pathogens. Few studies, however, have assessed the prevalence of and predictors for intestinal helminth infection among HIV-1–infected adults in urban African settings where HIV infection rates are highest. We collected and analyzed sociodemographic and parasitologic data from 297 HIV-1–infected adults (mean age = 31.1 years, 69% female) living in Lusaka, Zambia to assess the prevalence and associated predictors of helminth infection. We found at least one type of intestinal helminth in 24.9% of HIV-infected adults. Thirty-nine (52.7%) were infected with Ascaris lumbricoides, and 29 (39.2%) were infected with hookworm. More than 80% were light-intensity infections. A recent visit to a rural area, food shortage, and prior history of helminth infection were significant predictors of current helminth status. The high helminth prevalence and potential for adverse interactions between helminths and HIV suggests that helminth diagnosis and treatment should be part of routine HIV care.

A direct relationship exists between the intensity of hookworm infection and blood loss. Other parasites may also contribute to blood loss. Our objective was to assess the relationship between the intensity of soil-transmitted helminth infections and anemia in pregnant women in a highly endemic area of Peru. Recruitment occurred between April and November 2003. Overall, 47.31% of 1,042 women had anemia (hemoglobin < 11 g/dL), 47.22% were infected with hookworm and 82.25% with Trichuris. Prevalences of infections were not associated with anemia. However, those infected with moderate and heavy intensities of hookworm infection (OR = 1.84; 95% CI: 1.06, 3.17) and those with moderate and heavy intensities of both hookworm and Trichuris infections (OR = 2.13; 95% CI: 1.10, 4.13) were more likely to suffer from anemia than women having no or light intensities. These results support routine anthelminthic treatment within prenatal care programs in highly endemic areas.

Household water treatment is increasingly recognized as an effective means of reducing the burden of diarrheal disease among low-income populations without access to safe water. Oxfam GB undertook a pilot project to explore the use of household-based ceramic water filters in three remote communities in Colombia. In a randomized, controlled trial over a period of six months, the filters were associated with a 75.3% reduction in arithmetic mean thermotolerant coliforms (TTCs) (P < 0.0001). A total of 47.7% and 24.2% of the samples from the intervention group had no detectible TTCs/100 mL or conformed to World Health Organization limits for low risk (1–10 TTCs/100 mL), respectively, compared with 0.9% and 7.3% for control group samples. Overall, prevalence of diarrhea was 60% less among households using filters than among control households (odds ratio = 0.40, 95% confidence interval = 0.25, 0.63, P < 0.0001). However, the microbiologic performance and protective effect of the filters was not uniform throughout the study communities, suggesting the need to consider the circumstances of the particular setting before implementing this intervention.

The pre-membrane (prM) and envelope (E) genes of 41 viruses isolated from dengue fever (DF), dengue hemorrhagic fever (DHF), and dengue shock syndrome (DSS) patients from 1995 to 2002 were sequenced to determine the genetic variability of dengue 2 (DENV 2) viruses in the Philippines. The envelope sequence data were compared with a global sample of DENV 2 obtained from GenBank. Phylogenetic analysis revealed that two distinct genotypes, Asian 2 and Cosmopolitan, are currently circulating locally, each with the potential to cause severe hemorrhagic disease. After the initial isolation in 1998, the Cosmopolitan genotype has gradually and effectively replaced Asian genotype 2 in the Philippines. Members of this genotype were closely related to viruses from Australia, Singapore, and Thailand.

Recent studies have shown that West Nile virus (WNV) can induce an asymptomatic persistent infection in the kidneys of experimentally infected hamsters. The chronically infected rodents shed virus in their urine for up to 8 months, despite the disappearance of viremia and the development of high levels of neutralizing antibodies. WNV, like most members of the Japanese encephalitis virus complex (Flavivirus; Flaviviridae), is assumed to be mainly neurotropic; little is known about the genetic basis for its renal tropism. In this study, complete sequence analyses were done to compare four WNV isolates from the urines of persistently infected hamsters with the wild-type parent virus (NY 385-99). Nucleotide changes, ranging from 0.05% to 0.09%, were identified in all of the WNV isolates from urine; most of the changes were in coding regions, causing amino acid substitutions in the E, NS1, NS2B, and NS5 proteins. The genetic changes associated with renal tropism were also accompanied by a loss of virulence for hamsters and a change in plaque morphology.

Severe cases of hepatitis caused by hepatitis B virus (HBV) or hepatitis D virus (HDV) are often seen in the Brazilian Amazon, but there is a paucity of epidemiologic studies on viral hepatitis in this area. Thus, a cross-sectional study to investigate the prevalence of markers for HBV and HDV was performed. Serum samples were collected after participants completed an epidemiologic questionnaire. Markers for HBV and HDV were analyzed with an enzyme-linked immunosorbent assay. The HBV genotype was determined by sequencing of the gene for hepatitis B surface antigen (HBsAg). Of 2,656 samples, 89 (3.3%) were positive for HBsAg and 1,628 (61.5%) were positive for IgG antibody to hepatitis B core antigen. Markers for HDV were found in 47 cases (1.7%). Antibodies to HDV were associated with Amerindian ethnic origin, a lower educational level, a history of acute viral hepatitis, a history of malaria, male sex, a history of tattooing, and older age. The most frequent HBV genotypes were A and F. This study showed a high prevalence of HBV and HDV in the western Brazilian Amazon, as well as the predominance of HBV genotypes A and F.

A cross-sectional study of 77 patients infected with human immunodeficiency virus (HIV) in Khon Kaen, Thailand examined association of nutritional status with active opportunistic infections (AOIs)/HIV status and assessed degree of correlation between bioelectrical impedance analysis (BIA) and anthropometry. Many patients (41.3%) were malnourished using World Health Organization criteria for underweight, and malnutrition was associated with AOI status. Unconditional odds ratios (P < 0.05) for AOI as opposed to no AOI were 4.57 for underweight, 9.87 for severe underweight, 2.55 for triceps < 10th percentile, and 5.22 for mid-arm circumference < 10th percentile. Body fat composition from BIA, anthropometry, and body mass index were moderate to highly correlated (P < 0.001), with the highest correlation between BIA and subscapular skinfold (r = 0.86) and the lowest between BIA and triceps skinfold (r = 0.54). Insights were gained about relative value of using various measurements to assess nutritional status of HIV-infected populations.