Malaria vectors in the municipality of Serra do Navio, State of Amapá, Amazon Region, Brazil

We conducted a survey to determine the vectors of malaria in six localities of Serra do Navio municipality, State of Amapá, from 1990 to 1991. Malaria infection rates of 29.3 percent, 6.2 percent and 20.4 percent were detected by human blood smears in Colônia ægua Branca, Porto Terezinha and Arrependido, respectively. There was no malaria infection detected in Serra do Navio. Fifteen species were identified among 3,053 anopheline mosquitoes collected by human bait and 64.4 percent were identified as Anopheles albitarsis s.l., 16.7 percent An. braziliensis, 9.5 percent An. nuneztovari and 5.8 percent An. triannulatus. An. darlingi, the main vector of malaria in the Amazon region of Brazil, was scare. Using enzyme-linked immunosorbent assay (ELISA), a total positive rate of 0.8 percent (23/2876) was found for six species: fifteen An. albitarsis s.l., four An. nuneztovari, and one of each: An. braziliensis, An. triannulatus, An. oswaldoi and An. rangeli. Nine of 23 positive mosquitoes were infected with Plasmodium malariae, eight with P. vivax VK210, three with P. vivax VK247 and three with P. falciparum. Since An. albitarsis s.l. was collected feeding on humans, was present in the highest density and was positive by ELISA for malaria sporozoites, it probably plays an important role in malaria transmission in this area

Giardia lamblia: in-vitro sensitivity to some chemotherapeutic agents.

The susceptibility of Giardia lamblia to eight chemotherapeutic agents was studied in vitro. The criteria of viability of the parasite was the ability of the parasite to attach to the coverslip surface in situ, and to multiply in drug free media on subcultures. The giardicidal and 50% inhibitory concentrations of each drug were measured. The activity of metronidazole in vitro was found to be similar to that of mepacrine, whilst that of chloroquine was inferior. The sensitivity of G. lamblia to mepacrine and chloroquine is markedly greater than that reported for Entamoeba histolytica.