Distribution of paralytic toxins in California shellfish

Samples of Saxidomus nuttali and Mytilus californianus collected during the 1981 dinoflagellate bloom at Bodega Bay, California, were analyzed for the presence of paralytic toxins. Neck tissue of S. nuttali contained saxitoxin (STX) and neoSTX (95% of the total toxicity), whereas the bodies contained neoSTX and a mixture of the gonyautoxins. In a sample of M. californianus the presence of neoSTX and the gonyautoxins was demonstrated, whereas a second sample, collected at a different site, contained almost exclusively neoSTX.     

Soil-transmitted helminths and Plasmodium falciparum malaria: epidemiology, clinical manifestations, and the role of nitric oxide in malaria and geohelminth co-infection. Do worms have a protective role in P. falciparum infection?

Malaria and intestinal helminths are sources of significant morbidity worldwide. Given the nature of shared endemicity, these diseases often co-exist in the same populations. Therefore, much attention is now being given to the interaction between helminths and Plasmodium in the situation of co-infection. Existing evidence is consistent with the hypothesis that helminths are associated with continued and possibly increased incidence of malaria infection. However, data from some recent clinical fieldwork suggest protection from cerebral malaria in the setting of helminth co-infection. Nitric oxide, coupled with the immunoglobulin E (IgE) receptor, CD23, appears to be a crucial factor in preventing the development of cerebral malaria, thus improving chances for the survival of both host and parasite. In this work, we review literature on the subject of helminth and malaria co-infection, and offer a theoretical explanation of the helminth modulation of clinical malaria. In doing so, we advocate further research on this subject and also the need for a dual approach in global disease control intervention, which simultaneously targets both malaria and geohelminth infection.     

Canine visceral leishmaniasis, United States and Canada, 2000-2003

Visceral leishmaniasis, caused by protozoa of the genus Leishmania donovani complex, is a vectorborne zoonotic infection that infects humans, dogs, and other mammals. In 2000, this infection was implicated as causing high rates of illness and death among foxhounds in a kennel in New York. A serosurvey of >12,000 foxhounds and other canids and 185 persons in 35 states and 4 Canadian provinces was performed to determine geographic extent, prevalence, host range, and modes of transmission within foxhounds, other dogs, and wild canids and to assess possible infections in humans. Foxhounds infected with Leishmania spp. were found in 18 states and 2 Canadian provinces. No evidence of infection was found in humans. The infection in North America appears to be widespread in foxhounds and limited to dog-to-dog mechanisms of transmission; however, if the organism becomes adapted for vector transmission by indigenous phlebotomines, the probability of human exposure will be greatly increased.