Community-based assessment of safety and immunogenicity of the whole cell plus recombinant B subunit (WC/rBS) oral cholera vaccine in Peru.

Every year since its introduction in 1991, there have been epidemics of cholera in Lima, Peru. Vaccination is one approach to the control of cholera. A pilot study was conducted to assess the safety and immunogenicity of a whole cell plus recombinant B subunit (WC/rBS) cholrea vaccine in Lima, Peru. Five hundred and forty-one volunteers aged 2-65 years received two doses two weeks apart of WC/rBS vaccine or Escherichia coli K12 placebo administered in bicarbonate buffered water. Symptoms were monitored on all subjects and blood was collected from 102 persons before the first dose and two weeks after the second dose. Mild post-vaccination gastrointestinal symptoms were reported with equal frequency for both the vaccine and placebo recipients. Among 51 vaccines, 49% had a twofold or greater increase in serum vibriocidal titers (GMT = 78; range < 1:10 to 1:5120); and 92% and 82% developed a twofold or greater serum anti-cholera toxin IgG and IgA response, respectively. Persons with elevated prevaccination vibriocidal titers had a decreased response to the WC/rBS. Age and blood group did not affect the immune response. The WC/rBS vaccine was safe and immunogenic in a group of native Peruvians.

[Role of hepatitis B and delta viruses in the etiology of hepatocarcinoma and other chronic liver diseases]. / Rol de los virus de hepatitis B y delta en la etiología del hepatocarcinoma y otras hepatopatías crónicas.

We studied in a prospective form 23 patients with chronic hepatic disease of the Medicine Department in Regional Hospital of Cusco (Perú). It is a reference center of endemic places of B Hepatitis and Delta Hepatitis (Puerto Maldonado, Abancay y La Convención) (8). This study has been done in a year. The diagnosis was done by a hepatic biopsy in 16 patients, in the others in whom the biopsy was contraindicated, the diagnosis was clinic and the laboratory.

Antibodies to human T lymphotropic virus type I in a population from the Philippines: evidence for cross-reactivity with Plasmodium falciparum.

Residents of two areas in the Philippines were tested for human T lymphotropic virus type I (HTLV-I): Napsan, a site endemic for malaria, and a nonmalarious site, Bacolod. By ELISA, 30% of the 1743 Napsan residents were positive. Western blot immunoreactivity with two or more HTLV-I proteins was present in 81% of the ELISA positives; however, there was no reactivity with the env proteins. The frequency of this indeterminate immunoreactivity increased with the malaria antibody titer. None of the 200 Bacolod sera were Western blot immunoreactive. In competitive serologic assays, an HTLV-I lysate blocked the HTLV-I immunoreactivity of the Napsan sera but did not reduce malaria antibody. A Plasmodium falciparum lysate blocked both the HTLV-I and malaria immunoreactivity of the Napsan sera. These results show that indeterminate HTLV-I immunoreactivity can be caused by P. falciparum antibody. Serosurveys conducted in malaria endemic areas should consider this possibility.

In vitro growth inhibition of Plasmodium falciparum by sera from different regions of the Philippines.

Sera from different malaria endemic regions of the Republic of the Philippines were compared for their ability to inhibit growth of Plasmodium falciparum in vitro. Dialyzed serum was added to synchronous cultures containing schizonts for either the total 48 hr test period or only the last 24 hr in order to analyze the effects on erythrocytic invasion and intraerythrocytic growth, respectively. Reduction in 3H-hypoxanthine uptake was used to determine the percent of inhibition compared to nonimmune serum. One hundred seventy sera from Mindanao and Palawan in the South, the centrally located island of Mindoro, and Luzon in the North, were tested against 4 P. falciparum strains from the Philippines and 1 from Africa. Indirect fluorescent antibody titers were not predictive of inhibition. Inhibition of merozoite invasion rather than intraerythrocytic parasite growth is suggested by this study. Generally, sera were more inhibitory to parasite strains from the same geographical area than to those from more remote areas.

Survey of intestinal parasites on Palawan, Philippines.

A biomedical survey for intestinal parasites was conducted in Napsan on the island of Palawan, Philippines in September 1986. A total of 353 stool specimens were obtained from 155 males and 198 females ranging in age from 1 1/2 months to 70 years. Ascaris lumbricoides, 34.8%, hookworm 34.8% and Trichuris trichiura 25.2% were the most common helminths encountered, while Entamoeba coli 27.7% and Endolinax nana 22.2% were the common protozoans. This study demonstrated a 7-13% higher overall prevalence of intestinal parasites among the population on Palawan compared to previous studies in the rural Philippines.