The American Journal of Tropical Medicine and Hygiene - Volume s1-25, Issue 4, 1945

Attention is directed to the difficulties we have experienced in the propagation by either natural or artificial means of various strains of Plasmodium falciparum. Difficulties arising during the course of natural propagation are manifested by the failure of all or a part of the inoculations to take, even though performed by demonstrably infected mosquitoes. In view of the dissection criteria employed to check inoculations, it would not appear that the gametocyte level in the patient from whom the mosquitoes were infected has been a factor. Neither would it appear that refractoriness of the patients inoculated has been a frequent obstacle, since takes have commonly resulted on the reinoculation of such patients. An increasing proportion of failures is associated with increasing age of the sporozoites present in the mosquitoes, a characteristic of which we were already aware. This deterioration is more rapid than is the case with vivax sporozoites. However, since many failures occurred when fresh or relatively fresh sporozoites were used, this cannot be the sole factor involved. A further factor elicited results from the comparatively recent ingestion of quinine by the patient on whom the mosquitoes were infected. It has not prevented completion of the sporogonous cycle, but nevertheless it has impaired the vitality of the resulting sporozoites.

When certain of these strains were propagated artificially, gametogeny deteriorated suddenly or gradually. This change has been observed in strains propagated in colored patients. Its occurrence does not appear to be consequent on a heterologous immunity in the patients, since it has more commonly been observed in those presumed to be susceptible. This change does not appear related either to the administration of quinine to the patient or to its amount. When once initiated it appears to persist throughout subsequent passages, and we have not been able to overcome this deterioration.

Failure of gametogeny in strains of Plasmodium vivax which have been artificially propagated for extended periods in the application of malaria therapy has been reported. We succeeded in acquiring two strains with such a reputed characteristic, and, while these were being propagated on our service abundant gametocytes were detected, mosquitoes were infected, and infection was transmitted therewith. Our experience with this species of parasite leads us to suspect that reports of failure of gametogeny indicates lack of familiarity with the morphology of the vivax gametocytes on the part of the microscopists concerned. On the other hand, the morphology of the gametocytes of Plasmodium falciparum is sufficiently distinctive to render credible any reports of their presence or absence.

We wish to record the results of certain experiments performed to ascertain the degree of protection against the acquirement of malaria infections afforded by various dosages of quinacrine hydrochloride (atabrine) when administered to patients inoculated with one or more species of malaria parasites at varying levels of inoculation intensity.

The drug employed was furnished through the courtesy of the Winthrop Chemical Company, and was received in original 1000-tablet containers bearing the identifying number BTO27.

Patients were inoculated by the application of various lots of insectary-reared Anopheles quadrimaculatus which had been experimentally infected with Plasmodium vivax, McCoy strain, or Plasmodium falciparum, Costa strain. After the mosquitoes had been used, their salivary glands were removed by dissection and examined for the presence of sporozoites.

The patients were white adult males presumably susceptible to malaria infections. They were kept under observation and daily blood smears were taken, for a period of at least six months subsequent to the termination of the course of quinacrine.

From soldiers who had presumably acquired their infections in Pacific war areas, six strains of P. vivax were isolated by transfer of blood to patients who were candidates for malaria therapy. The clinical and parasitological characteristics of the induced infections were not unlike those of infections with McCoy strain of P. vivax, the strain of reference used throughout the study. Some of the patients with known or probable histories of former vivax infections demonstrated considerable immunity to the Pacific strain infections, four patients being refractory.

When gametocytemia of these induced infections seemed to favor mosquito infection, A. quadrimaculatus mosquitoes were fed. Subsequent to a minimum incubation period of 17 days, these mosquitoes were examined for sporozoites. Salivary gland infections were demonstrated in mosquitoes fed on patients with infections with three of the six strains. Sporozoite transmission of these three strains was accomplished. Subsequently the infectiousness to A. quadrimaculatus of patients with two of these strains was studied. It was found that salivary gland infections sometimes developed following the feeding of mosquitoes on patients with submicroscopic gametocytemia.

It is concluded that at least some of the vivax strains from the Pacific war area are capable of being transmitted by A. quadrimaculatus. It is believed that this mosquito is a somewhat less efficient vector for these strains than for McCoy vivax.

This is a report of two malaria parasite surveys made in the Amazon Valley during 1942 and 1943. The survey in December 1942 on 19,629 persons was made at the end of the dry season when the prevalence of malaria was expected to be lowest, and before control or prophylactic measures were undertaken. The survey in June 1943 on 27,103 persons from 37 localities was made at the end of the wet season when malaria incidence might be expected to be greatest. A study of hospital records on malaria cases in Belem before 1942 supported this assumption as to seasonal prevalence. The incidence of 3.3 per cent in June after control measures were instigated was shown to be lower than the incidence of 5.0 per cent at the expected low season in December.

Significant amounts of yellow fever virus have been recovered from the bodies of dead Aedes aegypti as long as 4 hours after death of the insect from exposure to ether, 17.5 hours after death from starvation, 20 hours after death from exposure to tobacco smoke, and 45.5 hours after death from exposure to potassium cyanide fumes.

On the contrary, following death from exposure to chloroform vapor, most of the virus activity was lost in 30 minutes and was totally absent in 1 hour.

Virus has been recovered from a significant number of lots of Haemagogus equinus and Haemagogus spegassinii which died of “natural causes” during the course of laboratory transmission experiments.

In studies such as those on the duration of immunity following yellow fever vaccination, it has been customary to use the results of the mouse protection test as a measure of the immune state; and in order to procure a time series, sera taken at various periods are compared in the same protection test run. This immediately raises the question of the effect of the storage on the older sera in the production of any differences of behavior between old and recent material.

There has been no satisfactory answer to this question, although a tentative approach to the problem has been made from time to time. Lloyd and Penna (1) compared the antibody content of desiccated and fresh immune serum over a period of nine months and concluded that there had been no demonstrable decline in antibodies in the desiccated material. These comparisons were made between desiccated sera from rhesus monkeys and fresh sera from the corresponding monkeys at the later periods.

• 1.  A cave harboring the tick Ornithodorus turicata, is reported from Denton County, Texas.
• 2.  The cave was identified as the Sam Bass Cave studied previously by Kemp and his associates.
• 3.  For the first time experimental evidence is presented that many of these ticks are naturally infected with the spirochete of relapsing fever and that they are able to transmit the infection to man and white rats.
• 4.  An attempt has been made to indicate the possible mechanisms through which the infection in this area apparently disappeared and reappeared.

The current treatment of African trypanosomiasis with antrypol or Bayer 205 and tryparsamide is usually effective. However, it is not ideal, and improved chemotherapeutic agents of reduced toxicity and higher effectiveness and greater ease of administration are desirable. It was with this in view that the present study of the effect of two new drugs on African sleeping sickness was undertaken.

These investigations were carried on in Liberia, West Africa, under the auspices of the American Foundation for Tropical Medicine, Inc. Through the courtesy of the Firestone Plantations Company, the hospital of the Firestone rubber plantation at Harbel, Liberia, was made available. Our patients were drawn from the native plantation laborers. These infected laborers came from different parts of Liberia where apparently the disease is established, but during the period that they remained on the Plantation proper, we consider that they were free from the risk of re-infection.

• 1.  The growth-promoting factor or factors for the blood and tissue flagellates studied are present in serum, but are not directly associated with albumin, euglobulin, pseudoglobulin or combinations of these three important fractions.
• 2.  Neither hemoglobin nor washed erythrocytes contain the necessary stimulant.
• 3.  This stimulant partially survives heating at 70°C. for 30 minutes, but is destroyed at 100°C.
• 4.  The factor or factors are not para-aminobenzoic acid, pyridoxin, nicotinic acid, thiamin nor any other vitamins tested.
• 5.  The essential stimulant is dialysable, and is probably lost during the process of fractionating the serum proteins.

The term “rodents” is often used to include all small mammals, particularly those of an injurious nature, yet, properly speaking, the rodents, Order Rodentia, are a definite zoological group best characterized by the chisel-like incisor teeth, four in number, and the absence of canine teeth. The rabbits, which were previously classed as a suborder of the rodents, are now placed by most mam-malogists in a separate order, the Lagomorpha, which was proposed by Gidley (1912). The rabbits differ markedly from the true rodents in their parasites, diseases, and reactions to disease.

Tularemia is stated by most writers to be a rodent disease but practically all have failed to distinguish between true rodents and rabbits.

Simpson (1929) states, “Tularemia exists primarily as an infectious disease of wild rodents particularly rabbits.”

Green (1931) says, “Tularemia is known to be a disease of rabbits as well as many other rodents.”

A third or perhaps fourth case of Madura Foot, caused by a species of Actinomyces, is described in a man who never left the United States. It is about the fortieth case of Madura Foot if cases caused by true fungi are included. A great number are probably never recognized but are treated as chronic osteomyelitis, sarcoma tuberculosis or syphilis. The writer knows three such cases, where the diagnosis was made following amputation. Treatment with penicillin and sodium propionate had no effect whatsoever, but sulfadiazine showed a fungistatic action, beginning with the disappearance of the fever and developing into a clinical cure.

The author's conclusion is that, from now on, every case of Actinomyces Madura Foot should be treated with doses of sulfonamides, sufficient to produce blood-levels of about 8 mgm. per cent, during at least three weeks and, if necessary, with repeated courses of this therapy. Advice to amputate the member should never be given before this is seriously tried. Because of the great similarity of the clinical picture of the cases of Madura Foot caused by Actinomyces and those caused by true fungi, the benefit of a trial with all the precautions mentioned above, should be given to every patient suffering from Madura Foot.

P.S. In July 1945 the old-patient came, on my request, in my office for controle. It was more than one year after his discharge. The foot showed a complete clinical cure. The man does all his heavy work as before the disease.

A uniform suspension was prepared from each of 46 fecal specimens selected because they were known to contain relatively large numbers of eggs of Schistosome mansoni. The number of eggs per cc. in each suspension was then determined by the Stoll dilution egg counting technique. The suspensions were examined by the routine diagnostic modification and also a semiquantitative modification of the acid-ether centrifugation technique and the zinc sulfate flotation technique and counts were made of the eggs recovered by the four methods. For twenty-five specimens found to contain over 400 eggs per cc., the results of the counts obtained by the various techniques were expressed in terms of the percentage of the available eggs that were actually recovered.

The acid-ether technique was found to be superior to the zinc sulfate flotation technique as a routine method for the isolation of schistosome eggs, recovering a greater number of eggs from 41 of the 46 specimens. In the group of 25 specimens, the acid-ether routine method gave an average percentage of 20.6% while the zinc sulfate counterpart gave an average of 4.6%. The semiquantitative modification of the acid-ether technique gave an average recovery of 48.2% while the zinc sulfate semiquantitative method gave an average recovery of 22.2%. The acid-ether preparations showed no distortion of the eggs, and usually contained less extraneous fecal debris than did the zinc sulfate preparations.

Although the acid-ether technique has inherent disadvantages the simplicity and efficiency of the method are such that it would appear to deserve further investigation as a routine diagnostic and survey procedure for the recovery of the eggs of Schistosoma mansoni. 4

• 1.  Concentrating procedures add nothing to specific identification but do increase survey incidence.
• 2.  ZNSO4 centrifugal flotation concentration is preferred for routine stool examinations.
• 3.  De Rivas centrifugation concentration is preferred for selected repeat examinations and preserved stocks.

This is a timely review of the rapidly expanding literature on Penicillin and allied substances.

Chapters on “The Production of Penicillin” and “The Administration and Dosage of Penicillin” are particularly well presented. The use of the substance locally and the methods of systemic administration are described in detail.

Following the general discussion on treatment, many diseases are discussed individually as to their therapeutic response to Penicillin. These include staphylococcic septicemia, subacute bacterial endocarditis, actinomycosis, pneumonia, gonorrhea, and syphilis.

The properties and clinical application of allied antibiotics are reviewed in less detail. Tyrothricin gramicidin S., Streptothricin, Patulin and Chlorophyll are included in the discussion.

The book sets forth a good deal of practical information. It will be of value to the practicing physician who is unfamiliar with antibiotic therapy.

In these days, when almost every month a new work appears upon Tropical Medicine, one naturally inquires into the reason for the appearance of any new work on the subject which is already covered by many excellent treatises of recent date. The authors believe that there is need for a concise work upon the subject and the Surgeon General of the Army, Major General Norman T. Kirk states in his “Foreword” “That there has long been need for a concise treatise in this field. While a large body of authoritative information exists in textbooks, the place for a convenient manual of tropical diseases has not been filled.” The reviewer, after carefully reading most of this book, agrees that it does fill the need for such a treatise and congratulates the authors upon the production of a work that should fill the needs of medical students and practicing physicians as well as of physicians serving in the Army, Navy and Marine Corps.