F. M. Feinsod

ACQUIRED IMMUNODEFICIENCY SYNDROME IN A HETEROSEXUAL POPULATION IN ZAIRE

38 patients with the acquired immunodeficiency syndrome (AIDS) were identified in Kinshasa, Zaire, during a 3 week period in 1983. The male to female ratio was 1.1:1. The annual case rate for Kinshasa was estimated to be at least 17 per 100 000. Opportunistic infections were diagnosed in 32 (84%) patients, disseminated Kaposis sarcoma (KS) with opportunistic infection in 5 (13%), and disseminated KS alone in 1 patient. Immunological characteristics of these patients were as reported for cases in the USA and Europe, but immunological abnormalities were also found in 6 controls with infectious diseases but no symptoms of AIDS. Female AIDS cases were younger than male patients with AIDS (mean ages 28.4 vs 41.1 years, respectively), and were more often single (14/18 vs 2/20). Homosexuality, intravenous drug abuse, and blood transfusion did not appear to be risk factors in these patients. The findings of this study strongly argue that the situation in central Africa represents a new epidemiological setting for this worldwide disease--that of significant transmission in a large heterosexual population. Two instances of clusters of AIDS (not included in the above series) involving males and females with frequent heterosexual contact further implicate heterosexual transmission.

Survival estimates for adult Culex pipiens in the Nile Delta

In an endemic area for Wuchereria bancrofti filariasis in the Nile Delta, survival of adult female Culex pipiens was estimated by parity rate, mosquito infection and infectivity rates. Infection rates and 4th instar larval populations, as well as infection and parity rates, were linearly correlated. Infectivity correlated only with parity rates. These associations corresponded to parallel changes in ambient temperature. Although survival calculated from parity rates measured longevity of both infected and non-infected Cx. pipiens, survival based on infection and infectivity was a more reliable indicator for parasite transmission.

The epidemiology of human visceral leishmaniasis in El Agamy (Alexandria Governorate), Egypt: serosurvey and case/control study.

In Alexandria Governorate, Egypt, 27 cases of visceral leishmaniasis (VL) were detected from 1982-1985 through active and passive case detection. Twenty-two were located in El Agamy, a resort town of 50,000 residents located 15 km west of the City of Alexandria. To describe the disease focus, eight areas of 100-200 households in El Agamy were mapped and censused. All individuals were examined clinically, and blood was obtained by finger stick to measure leishmanial antibodies by radioimmune assay. Two case/control studies were carried out in the mapped areas. In one study, case households were more often found near open garbage containers than were control households. In a second case/control study, houses with cases of VL or seropositive individuals were found more likely to face open areas. These results demonstrate that characteristics of houses which could increase exposure to reservoir hosts can be associated with VL or leishmanial seropositivity. This suggests that control programmes should improve garbage disposal and should focus on houses located in peripheral areas of the community.

The discovery and preliminary characterization of a novel trypanosomatid parasite from Rattus norvegicus and stray dogs from Alexandria, Egypt

A survey of rodents and dogs was carried out in Alexandria and its environs to see if an animal reservoir was associated with an outbreak of infantile kala-azar in this area. Three rodent species, Rattus rattus, Rattus norvegicus and Mus musculus, were commonly trapped and examined. A flagellate parasite was isolated from the spleens of two R. norvegicus. It was typed serologically by excreted factor serotyping and enzymologically by thick starch electrophoresis of four of its enzymes: GPI, G6PD, 6PGD and PGM. The same type of parasite was also isolated from two stray dogs from the same vicinity. This flagellate was quite distinct from Leishmania donovani, Leishmania major and Leishmania tropica, the three common Old World species of Leishmania; but its exact identity remains uncertain. It could be a new leishmanial entity or a flagellate parasite of another genus.

Human cutaneous leishmaniasis in two communities in eastern Sinai, Egypt.

Cutaneous leishmaniasis (CL) (L. major) has been documented in soldiers of the Multinational Force in the Sinai as well as in visitors to the area. However, little is known about the prevalence of this disease in the local populations. We identified 2 villages in northeastern Sinai near the infected camps of the Multinational Force and, in a population-based study, measured the prevalence of CL.Populations studied included residents in 2 towns as well as a Bedouin family living on the village periphery. Leishmanial parasites were identified from smears taken from cutaneous lesions. Three of 90 residents in I village and 3 of 8 Bedouins had CL. None of 43 residents examined in the second town had CL. Two of 6 individuals had multiple lesions, and at least I had recurring ulcers. Five of the 6 affected individuals were males and the 6 represented all age groups. The 6 infected individuals came from 3 families. Infected individuals had traveled outside of the village more frequently than uninfected individuals, suggesting that transmission was more common outside of residential areas.

Immunosuppressive medication associated with leishmanial antibodies in adults residing in an endemic focus of infantile visceral leishmaniasis—a case/control study

In a focus of infantile visceral leishmaniasis in Al Agamy (Alexandria), Egypt, adults were found by radioimmune assay to have leishmanial antibodies. This finding was unexpected, and an explanation was sought. Seropositive adults and age- and sex-matched seronegative controls were interviewed to ascertain possible predisposing risk factors. Ten of 16 seropositive individuals were taking corticosteroids compared to one of 22 seronegative individuals (P = 0.0002). Two seropositive individuals (one woman and one man) were taking phenylbutazone, and two women were taking female sex hormones. The association between immunosuppressive medication and leishmanial seropositivity suggests that acquired changes in host population immunocompetence may significantly alter age-specific seroprevalence of leishmanial antibodies.