Community awareness and risk of rabies associated with exposure to animals in India.

BACKGROUND: Rabies is a fatal but preventable disease. Around the world, awareness studies about rabies have been widely used to understand the disease and in its preventive measures. OBJECTIVES: The present study was conducted to assess the awareness of rabies as a disease, its transmission, and prevention among the general population and also to assess the perceived health risks associated with exposure to animals. METHODS: A cross-sectional study was undertaken across seven representative states in India between July and November 2017. Multistage sampling methodology was followed to select 1012 households as the primary sampling unit, and one adult responsible respondent from each household was interviewed as study participants. RESULTS: Six hundred and eleven (60.4%) participants had heard of rabies. Only 0.2% had extensive knowledge of rabies. Majority (440, 72.0%) of the participants considered rabies as a fatal disease; 77.3% opined that risk of rabies from dogs was high compared to 41.6% who believed that there was little or no risk of rabies from cats. Only 37 (3.7%) participants were aware about preexposure prophylaxis. CONCLUSION: The awareness on rabies and its prevention in the study population was not satisfactory.

A coverage evaluation survey of JE vaccination in two districts of Karnataka.

A coverage evaluation survey was conducted in Mandya and Koppal districts of Karnataka state following the Japanese Encephalitis (JE) vaccination campaign. The purposes of the survey were to assess coverage of children in target age group by JE vaccination and to assess adverse events following immunisation against JE, the knowledge of health care providers and community about JE & mass vaccination for JE. The study design consisted of both quantitative and qualitative methods. The quantitative data was used to know the coverage levels for children. The qualitative data collected through interviews of head of the family in the sample households, selected health care workers using a structured pretested questionnaire. The standard cluster sampling method was used for selecting the sample of children to be evaluated. In Mandya district the evaluation showed 92% coverage in the selected sample of 313 children against the reported 83.85%. In Koppal district the evaluation showed 70% coverage, among the selected sample of 251 children, against the reported coverage of 69.8%. The incidence of adverse events was 4% in Mandya sample and 6.37% in Koppal sample. In Mandya district, about 42% of households had knowledge of JE. About 68% of households had prior knowledge of the immunization day. In Koppal district, the survey has revealed that only 19.85% of the heads of household had the knowledge of JE and 48.53% had the knowledge of JE vaccination before the day of vaccination campaign.

An immunogenicity, safety and post-marketing surveillance of a novel adsorbed human diploid cell rabies vaccine (Rabivax) in Indian subjects.

In 1999, Serum Institute of India indigenously developed an adsorbed human diploid cell rabies vaccine (Rabivax). During 2000-04, this new vaccine was subjected to a series of immunogenecity and safety studies. Initially, an experimental batch of Rabivax (adsorbed) was assessed on ten healthy adult volunteers and its response was comparable with that of Merieux inactivated rabies vaccine (MIRV, lyophilized) which was used as a control. Subsequently, Rabivax (adsorbed) was assessed on forty-five suspect rabid dog bite cases with MIRV as control. The vaccine was found to be equally safe and immunogenic as MIRV and showed better rabies virus neutralizing antibody (RVNA) response on day 90 than MIRV. A post-licensing study conducted on 150 cases of suspect rabid animal bites showed it to be safe and immunogenic. To assess its long-term sero-efficacy some of these subjects tested after one year of follow up showed that 84% of them had adequate RVNA titers. In addition, a routine post-marketing surveillance done on 1608 animal bite cases demonstrated that Rabivax (adsorbed) was safe and efficacious. The adverse events to Rabivax (adsorbed) included pain at injection site (3.4%), swelling with induration (2.8%), fever and headache (1.4%). No serious adverse event was reported from the studies. In conclusion, Rabivax (adsorbed) is an immunogenic, safe and efficacious vaccine for rabies prophylaxis in humans.

Assessing the safety of post-exposure rabies immunization in pregnancy.

Fourteen pregnant women who received rabies post-exposure prophylaxis (PEP) at the anti-rabies clinic (ARC) of Kempegowda Institute of Medical Sciences (KIMS) were followed up for assessing the safety of modern rabies vaccines and equine rabies immunoglobulin (ERIG) in pregnancy. The women were in the age range of 18-28 years, mostly from urban area (64%) and exposed to suspect rabid dogs (86%). They had received purified vero cell rabies vaccine (Verorab = 8 and Abhayrab = 4), purified chick embryo cell vaccine (Rabipur = 2) by Essen regimen; and equine rabies immunoglobulin (Equirab = 7 and Pasteur anti-rabies serum = 1). None of the pregnant women reported any adverse events to either vaccine or equine rabies immunoglobulin. All had safe vaginal deliveries and in all cases both the mother and the child were found to be healthy and normal.

Assessing the relationship between antigenicity and immunogenicity of human rabies vaccines. Results of a meta-analysis.

A meta-analysis was done to study the relationship between antigenecity and immunogenecity of human rabies vaccines. The data of ten cell culture human rabies vaccine studies conducted at a single centre during 1993-2004 were used in the study. The vaccines studied included Purified Chick Embryo Cell Vaccine (Kaketsuken, Japan and Rabipur, India), Purified Vero cell Rabies Vaccine (Verorab, France), Human Diploid Cell Vaccine (MIRV, France and Rabivax, Adsorbed and Lyophilized, India) and Rhesus Diploid Rabies Vaccine (adsorbed, USA). Interestingly, it was revealed that an higher antigenecity of rabies vaccines viz. potency of > or = 5 IU per single intramuscular dose did not result in significantly higher immunogenecity, as measured by rabies virus neutralizing antibody (RVNA) titers in the vaccinees, both on day 14 (t = 0.42, p > 0.66, GMR = 1.06, 95% CI of GMR = 0.82, 1.37) and day 90 (t = 0.80, p > 0.43, GMR = 1.15, 95% CI of GMR = 0.74, 1.14). However, as there are no reports of meta-analysis of cell culture human rabies vaccine trials, to confirm this observation the authors recommend further studies in this regard.

Simulated post-exposure rabies vaccination with purified chick embryo cell vaccine using a modified Thai Red Cross regimen.

OBJECTIVES: Currently, two intradermal regimens for the administration of cell culture rabies vaccines are approved by the WHO for rabies post-exposure prophylaxis: the two site Thai Red Cross regimen (TRC) and the eight site regimen. For the TRC regimen the volume of vaccine recommended per dose is 0.1 ml of purified Vero cell rabies vaccine (PVRV) and 0.2 ml of purified chick embryo cell vaccine (PCEC). The objective of the present study was to evaluate comparatively the immune response to PCEC and PVRV vaccines administered by the TRC regimen using a uniform dose of 0.1 ml of vaccine. METHODS: Forty-two subjects received TRC regimen (2-2-2-0-1-1) with 0.1 ml of PCEC vaccine and 38 subjects received the same regimen with PVRV. The rabies neutralizing antibody response in these subjects on days 10, 28, 90 and 180 was determined by the standard mouse neutralization test (MNT). RESULTS: There was adequate antibody response with both the vaccines and 100% seroconversion was observed by day 10. Furthermore, the antibody titers obtained with PCEC did not differ significantly from those obtained with PVRV on all days tested (p > 0.05). CONCLUSIONS: It can be concluded from the results that an adequate antibody response can be obtained with PCEC vaccine when administered by the TRC regimen even after reducing the quantity of vaccine from 0.2 ml to 0.1 ml per intradermal dose. The feasibility of using this regimen in true post-exposure cases needs to be further evaluated.