Antimalarial measures--type, sources of advice and compliance among tourists to Natal/KwaZulu.

Typical advice on antimalarial measures provided by pharmacies as well as actual behaviour in this regard and sources of advice accessed by tourists to northern Natal/KwaZulu were canvassed by telephonic interviews with 70 pharmacies and 53 'care providers' (members of travel parties). Doctors (26%) and pharmacists (40%) were the most commonly approached sources of antimalarial advice. Professional recommendations frequently involved chloroquine-based drugs (80% of recommended drugs), despite the chloroquine-resistant status of the study area. Drug choice reflected the limited availability of new alternatives to chloroquine at the time the study was conducted, as well as ignorance of drug resistance in the area. Possible reasons for the inappropriate nature of many of the reported recommendations, as well as an approach to the dissemination of future prophylactic policy documents, are discussed.

Assessment of the residual efficacy of lambda-cyhalothrin. 2. A comparison with DDT for the intradomiciliary control of Anopheles arabiensis in South Africa.

There are several factors that support the need to assess the efficacy of potential alternative insecticides to DDT for malaria vector control. The objectives of this study were to evaluate the persistence and efficacy against Anopheles arabiensis of lambda-cyhalothrin used as an intradomiciliary insecticide in daub huts and to compare its efficacy in this regard to DDT. Exit trap catches showed the population of An. arabiensis was high during the months of January to March, with a peak in February. During all months, the number caught leaving lambda-cyhalothrin-sprayed huts was markedly less than the number from both control and DDT-sprayed huts. The percentage survival of bloodfed mosquitoes ranged from a low of 55% caught leaving the lambda-cyhalothrin-sprayed huts, to 82% of those caught leaving DDT-sprayed huts. The percentage of bloodfed mosquitoes caught leaving huts was high (> 60%). The survival of unfed mosquitoes was low, even from the control huts (43%).

Bacteriological investigation of the occurrence and antibiotic sensitivities of the gut-flora of the potential southern African medicinal leech, Asiaticobdella buntonensis (Hirudinidae).

The lack of availability of medicinal leeches is a major impediment to the widespread use of leech therapy for treatment of congested flaps and replants in southern Africa. An investigation into the suitability of an alternative leech, the indigenous southern African leech, Asiaticobdella buntonensis, was therefore started. The risk of hospital-acquired infection related to the use of leeches and the antibiotic sensitivities of bacteria isolated from the gastro-intestinal tract of wild-caught leeches were investigated. Eleven bacterial genera were isolated but Aeromonas were most frequently isolated, occurring in 82% of microbiological samples. All were sensitive to cefotaxime and amikacin. The gut-flora and their sensitivities to 19 antibiotics were similar to those reported for the traditional medicinal leech, Hirudo medicinalis. These results emphasize the need to anticipate unusual infections when prescribing prophylactic or curative antibiotics in the course of leech therapy.

The persistence of hepatitis B antigen in the bloodmeal of the potential medicinal leech, Asiaticobdella buntonensis.

The persistence of the hepatitis B virus surface antigen (HBsAg) was used as an index of the survival time of this virus within the gastro-intestinal tract of the potential southern African medicinal leech, Asiaticobdella buntonensis. HBsAg was tested for in blood/faecal material at five intervals over 15 weeks. Samples from both the midgut and the rectum remained positive for the entire test period, although with decreasing strength. The results are compared with reports on other arthropods which indicate increasing antigen persistence with increasing body size. The findings implicate medicinal leeches as mechanical vectors of HBV and possibly of other medically important viruses, and argue against using leeches of suspect or unknown origin in the alleviation of venous congestion in failing microsurgical procedures.