Serological evidence of rickettsial infections in Delhi.

Background & objectives: Rickettsial infections remain under-diagnosed due to lack of diagnostic facilities in developing world. Here we present our experience at National Centre for Disease Control, Delhi, about a serosurvey done in Delhi for rickettsial disease with easy to perform low cost, low expertise Weil Felix test. Methods: On the basis of cut-off titre obtained in healthy population, Weil Felix test results were interpreted along with clinical data. Entomological investigation was also carried out in select areas of Delhi. Rodents were trapped from houses and gardens and vector mites were collected. Results: When serum samples were collected during initial 5 yr period from patients with fever of unknown origin, seropositivity was 8.2 per cent whereas when rickettsial infection was kept as one of the differential diagnosis by clinicians seropositivity increased to 33.3 per cent. Rickettsial infections detected were scrub typhus (48.2%) followed by spotted fever group (27.5%) and typhus group (6.8%) during 2005-2009. In preliminary entomological survey vector mite Leptotombidium deliense was found on rodents. Interpretation & conclusions: Our findings showed that results of Weil Felix test should not be disregarded, rather clinically compatible cases should be treated to save lives.

Investigation of an outbreak of chikungunya in Malegaon Municipal areas of Nasik district, Maharashtra (India) and its control.

BACKGROUND & OBJECTIVES: An outbreak of chikungunya fever occurred in Malegaon town of Nasik district of Maharashtra state, India during February and March 2006. A total of 4530 fever cases were reported during this period including 1781 cases which were admitted in different hospitals of the town. An entomological and epidemiological investigation was carried out in the affected villages during the outbreak to study the possible causes of the outbreak and to isolate the virus responsible. METHODS: Entomological evaluation was done as per WHO guidelines. Sera samples were collected by venipuncture from clinically suspected chikungunya patients in hospitals and also during house-to-house survey in affected villages. IgM antibodies to dengue virus were detected using IgM capture ELISA (PANBIO) and by "Haemagglutination inhibition test" for detection of antibodies against Chikungunya virus. Acute sera samples were inoculated in cell lines for virus isolation. The isolates were confirmed by RT-PCR. RESULTS: On investigation, it was found that water storage containers like cement tanks, plastic containers or earthen pots placed in front of the individual houses were the potential breeding sites for Aedes aegypti. Entomological survey carried out in the most affected areas revealed high Aedes indices. House, container and breteau indices were found to be 27.2, 16.19 and 35.1, respectively. Out of the 13 acute sera samples collected, virus was isolated in 10 samples. The isolates were confirmed by RT-PCR and sequencing using primers from nsP1 gene of Chikungunya virus (CHIKV, Accession No. EF077609, EF077610). Of the 17 convalescent sera tested, significant level of HI antibodies to CHIKV was detected in five samples. One sample was positive for IgM antibodies against dengue virus. Based on clinico-epidemiological features and laboratory findings, the illness was confirmed to be of chikungunya viral disease. CONCLUSION: Control measures targeting the vector population and personal protective measures against the mosquito bites were instituted. Extensive IEC campaign with the involvement of community and religious leaders helped in containment of the disease.

Knowledge, attitude and practices about animal bites and rabies in general community--a multi-centric study.

Rabies a disease as old as our civilization, continues to be the most feared of all communicable diseases. Despite the availability the state-of-the-art tools which ensure near cent percent protection against rabies, India is the largest contributant to rabies mortality in the world. A multicentric study was carried out from April 2001 to September 2002 with the objective of assessing the knowledge, attitudes, beliefs and practices (KAP) about animal bites and rabies in the general community. The proforma for interviewing the general community was developed and used after field testing. The study was carried out at six selected centres across the country viz. Delhi, Hyderabad, Raipur, Jamnagar, Coonoor and Rajahmundry and was co-ordinated by National Institute of Communicable Diseases (NICD), Delhi, after thorough briefing of designated nodal officers. A total of 1129 (male: female :: 48.5: 51.5) persons in the age group of 18 to 80 years were interviewed in this study. Of these about 751% of the individuals had attended school at some level and rest were illiterates. 68.7% people had heard about rabies. In 60.7% of cases the community associates rabies with dog bite only. Knowledge about appropriate wound toilet was found to be inadequate. Only 360 (31.9%0/) people felt that washing the wound with soap and water was the best option. Application of indigenous products like chillies (11.4%), turmeric (5.6%), lime (6.8%), kerosene oil (2.3%), herbal paste (4.2%) etc was suggested along with visit to occult medicine practitioner (1.5%) as part of the bite wound management. People were not aware of number of injections needed for treatment of animal bites. Multiple reasons viz negligence and ignorance 354 (31.4%), fear of multiple painful injections 365 (32.3%), expensive treatment 169 (15%) and long course requiring daily visits to anti-rabies clinics 73 (6.5%) were cited as reasons for non-compliance of treatment. KAP study suggests that there is need to create awareness amongst the masses regarding epidemiology of the disease and merits of prompt and appropriate post exposure treatment through enhanced IEC activities.

Comparative evaluation of commonly used laboratory tests for post-mortem diagnosis of rabies.

Animal brain samples received at WHO Collaborating Centre laboratory at National Institute of Communicable Diseases (NICD) during the years 1991-2002 were tested by Seller's stain, Fluorescent Antibody Test (FAT) and Mouse Innoculation Test (MIT) as methods of rabies diagnosis. Negri bodies on Seller's staining could be detected in 52.5% of MIT positive brains, the concordance of this test with MIT was found to be 77.8%. FAT was positive in 91.5% of MIT positive brains, though it showed concordance of 95.7% with MIT results in the total samples. 12.2% of the samples were found positive by FAT of which 1/3rd also showed the presence of Negri bodies when MIT was negative i.e. showing that the virus is present in inactivated form. Thus emphasizing the need for timely and proper collection and transportation of specimens for testing. Seller's stain and FAT give reliable diagnosis of rabies in the brain samples in majority of the cases. MIT being time-intensive test, is of academic value only in decision making as regards initiation of Post Exposure Treatment (PET), it is recommended that in cases where Seller's stain and FAT have yielded negative results the decision to initiate PET should give due consideration to the nature and circumstances of the animal bite and other epidemiological features.

Safety and immunogenicity of the intradermal Thai red cross (2-2-2-0-1-1) post exposure vaccination regimen in the Indian population using purified chick embryo cell rabies vaccine.

PURPOSE: To test the immunogenicity of the WHO recommended "2-2-2-0-1-1" post-exposure rabies vaccination regimen in Indian subjects to determine the feasibility of replacing crude sheep brain nerve tissue rabies vaccine with modern tissue culture rabies vaccine at major anti-rabies treatment centers throughout India. METHODS: Purified chick embryo cell vaccine (PCECV) was administered in the dosage of 0.1 mL per site to 53 Indian subjects. RESULTS: All subjects produced rabies antibodies above 0.5 IU/mL by day 14 post-vaccination. Only minor adverse reactions including swelling (6.6%), erythema (5.4%) and pain (1.4%) were observed for which no treatment was required. CONCLUSIONS: This study demonstrated that PCECV is safe and highly immunogenic in Indian subjects when administered intradermally as 0.1 mL/site using the "2-2-2-0-1-1" post-exposure regimen.

Human rabies in Delhi.

OBJECTIVE: Analysis of human rabies cases admitted in Infectious Diseases Hospital, Delhi during the course of one year was undertaken to understand the epidemiology of rabies. METHODS: The data was collected using standardized proforma and was analyzed on EPI Info 6.02 software version. A total of 49.8% of the human rabies came from Delhi and rest belonged to adjoining states of UP (30.3%), Haryana (18.3%), Bihar (0.8%), Punjab (0.4%) and MP (0.4%). Children in the age group 5-14 years fell victim to the disease in significantly higher numbers (36.7%) as compared to other age groups. Male Female ratio was 4:1. Biting animals involved were dog (96.7%), jackal (1.7%), cat (0.8%), monkey (0.4%) and mongoose (0.4%). Majority (78.8%) had Category III exposure. Hydrophobia, which is the pathogonomic feature of human rabies, was present in 95% of cases. Remaining (5%) gave history of animal bite and presented with features of aerophobia, photophobia along with fever, weakness in limbs, parasthesia, and/or paralysis. Significantly higher number (93.4%) did not receive any local wound treatment. Most (91.7%) cases never received any vaccination and remaining were inadequately vaccinated; only five had received 10-14 injections of Neural Tissue Vaccine (NTV) and one child who had multiple bites on face, received 5 doses of NTV, local wound treatment and intramuscular ARS on 3rd day. RESULT: The data strongly reveals that people who died due to rabies either did not receive any treatment or were inappropriately and inadequately treated. Hence, there is need to educate the community and the health care professionals about the importance of immediate and adequate post exposure treatment. The data also indicates that the epidemiology of the disease has not changed much over the decades. CONCLUSION: The disease can be prevented with the available tools and all we need to do is to implement them effectively.

Animal bites: the current management guidelines.

Rabies is a major public health problem in India. It is mainly transmitted by stray dogs, which form an overwhelming population in the country. Dogs are responsible for upto 95% of animal bites requiring antirabies treatment. In view of the exceptionally high fatality rate of human rabies, the prevention of infection after exposure is of utmost importance. With the availability of safe and effective tissue culture vaccines prevention of this dreaded disease is virtually assured by immediate and appropriate post exposure treatment. This is a three pronged approach including proper wound management, judicious use of antirabies serum and modern tissue culture vaccines. In India, Neural Tissue Vaccine is still used for post exposure treatment in public sector, though effective, this vaccine has serious side effects. The production and use of tissue culture vaccine should be encouraged with the aim to phase out neural tissue vaccine. WHO recommends use of intradermal route of inoculation of Tissue Culture Vaccine which makes the treatment very economical. However, this route as yet, is not approved by Drug Controller, Government of India (DCGI). There are no uniform guidelines for management of animal bite cases in India. In this article an attempt is made to discuss various aspects of animal bite management.

Immunogenicity of purified chick embryo cell anti-rabies vaccine in post-exposure treatment of animal bite cases.

The observations on immunogenicity of Purified Chick Embryo Cell (PCEC) anti rabies vaccination in post-exposure prophylaxis is reported. In total 207 serum samples collected from patients receiving 3 to 6 doses of PCEC were analysed for the presence of anti-rabies antibodies. The samples were collected from 10 days to 11 months after the last dose of vaccine. All the vaccinees (n=33) tested after 3 doses of PCEC showed protective titres (> or = 0.5 IU/ml) and those receiving 5-6 doses (n=161) showed 4-5 times higher than protective titres. The analysis pertains to specimens collected at one point of time only after the vaccination. However, in all 17 vaccinees where samples were collected 7-11 months after 3-6 doses of vaccine, the protective titres were sustained, these being 3-4 times higher than the protective titres in those receiving 5-6 vaccine doses. The results indicated that there was no need of routine anti-rabies antibody monitoring in healthy individuals receiving post-exposure prophylaxis in recommended doses of vaccine.