Persistent arthralgia among Chikungunya patients and associated risk factors in Chennai, South India.

CONTEXT: Chikungunya (CHIK) fever is viral disease characterized by joint pain for prolonged duration in various settings. However, there are no reports of long-term follow-up of the CHIK patients from India. AIMS: We conducted a cohort study to describe the clinical manifestations, incidence of persistent arthralgia, and the associated risk factors among patients with CHIK identified during an outbreak in a suburb of Chennai, India. MATERIALS AND METHODS: We conducted a retrospective cum prospective cohort study in Gowripet, Avadi, Chennai. We included all adult CHIK case patients identified during the outbreak. We conducted a nested case-control study to identify the risk factors for persistent arthralgia defined as a CHIK case experiencing arthralgia for more than 15 days from the date of onset of illness. We included all 81 patients and 81 randomly selected controls. RESULTS: All 403 case patients had joint pain. Approximately 40% suffered joint pain for up to 1 month and 7% had it beyond 1 year. The most commonly affected types of joints were knee (96%), wrist (80%), and ankle (77%) joints. Regarding the number of types of joints affected, 36% had six types of joints, 23% had five types of joints, and 14% had three types of joints affected. The overall incidence of persistent arthralgia was 80%. High-grade fever, involvement of four or more types of joints, and joint swelling were significantly associated with persistent arthralgia. CONCLUSIONS: High prevalence of persistent arthralgia indicates the need for appropriate treatment strategies to reduce the severity and duration of joint pain.

Quality of comprehensive assessment among severely ill TB patients referred after triaging in southern India.

To reduce TB deaths, Tamil Nadu, a southern Indian state, implemented the first state-wide differentiated TB care strategy starting April 2022. Triage-positive severely ill patients are prioritised for comprehensive assessment and inpatient care. Routine program data during October-December 2022 revealed that documentation of total score after comprehensive assessment was available in only 39%, possibly indicating poor quality of comprehensive assessment. We confirmed this using operational research. The case record form to record comprehensive assessment was used only in 26% and among these, the completeness and correctness in filling out the form were sub-optimal. There is a clear need to enhance the quality of comprehensive assessments.

Depuis avril 2022, le Tamil Nadu, un État du sud de l'Inde, a mis en œuvre la première stratégie de soins différenciés pour la TB à l'échelle de l'État afin de réduire le nombre de décès dus à la TB. Les personnes gravement malades ayant obtenu un résultat positif au triage sont prioritaires pour une évaluation complète et des soins hospitaliers. Les données du programme de routine entre octobre et décembre 2022 ont révélé que la documentation du score total après l'évaluation complète n'était disponible que dans 39% des cas, ce qui pourrait indiquer une mauvaise qualité de l'évaluation complète. Nous l'avons confirmé par le biais d'une recherche opérationnelle. Le formulaire de dossier pour enregistrer l'évaluation complète n'a été utilisé que dans 26% des cas et, parmi ceux-ci, l'exhaustivité et l'exactitude du remplissage du formulaire n'étaient pas optimales. Il est manifestement nécessaire d'améliorer la qualité de l'évaluation complète.

Risk factors associated with death among influenza A (H1N1) patients, Tamil Nadu, India, 2010.

BACKGROUND: Limited information is available about the risk factors associated with death among patients of influenza A (H1N1) in India. AIMS: To describe the epidemiology of laboratory-confirmed influenza A (H1N1) patients and identify risk factors associated with death. SETTINGS AND DESIGN: We reviewed the surveillance data of laboratory-confirmed patients in Tamil Nadu, India, for the year 2010. We conducted a case-control study by comparing 70 laboratory-confirmed A (H1N1) patients who died (cases) with 210 A (H1N1) patients who recovered (controls) to identify the risk factors for deaths. MATERIALS AND METHODS: We interviewed the controls and immediate care-takers of the influenza patients who died to collect information about socio-demographic details and co-morbid conditions. We used an abstraction form to collect the information about the clinical details from the case records of the hospitals where the cases and controls received treatment. STATISTICAL ANALYSIS: We analysed the surveillance data by time, place and person. We conducted univariate and multivariate logistic regression analysis for identifying factors associated death. RESULTS: During 2010, 1302 laboratory-confirmed cases were reported to the Tamil Nadu surveillance unit. Of these, 72 patients died (case fatality=5.5%). About 2/3 of the cases and 40% of the deaths were from three districts. On multivariate analysis, past history of diabetes, treatment in private hospitals, treatment with corticosteroids during illness, visit to >1 healthcare facility before laboratory confirmation and delay of >48 h in starting antivirals were found to be independently associated with the deaths. CONCLUSIONS: Influenza patients with previous history of diabetes, who had treatment with corticosteroids during illness, and started with antivirals after 48 h of onset of symptoms, were at higher risk of adverse outcome. In order to reduce the risk of death during future waves of influenza in Tamil Nadu, the physicians need to be sensitised regarding (1) higher risk of adverse outcomes among A (H1N1) patients with diabetes; (2) adherence to the national protocol for categorisation of cases; (3) prompt initiation of antivirals for severe cases; and (4) avoidance of systemic corticosteroids during management.

Added value of the measles-rubella supplementary immunization activity in reaching unvaccinated and under-vaccinated children, a cross-sectional study in five Indian districts, 2018-20.

INTRODUCTION: Supplementary immunization activities (SIAs) aim to interrupt measles transmission by reaching susceptible children, including children who have not received the recommended two routine doses of MCV before the SIA. However, both strategies may miss the same children if vaccine doses are highly correlated. How well SIAs reach children missed by routine immunization is a key metric in assessing the added value of SIAs. METHODS: Children aged 9 months to younger than 5 years were enrolled in cross-sectional household serosurveys conducted in five districts in India following the 2017-2019 measles-rubella (MR) SIA. History of measles containing vaccine (MCV) through routine services or SIA was obtained from documents and verbal recall. Receipt of a first or second MCV dose during the SIA was categorized as "added value" of the SIA in reaching un- and under-vaccinated children. RESULTS: A total of 1,675 children were enrolled in these post-SIA surveys. The percentage of children receiving a 1st or 2nd dose through the SIA ranged from 12.8% in Thiruvananthapuram District to 48.6% in Dibrugarh District. Although the number of zero-dose children prior to the SIA was small in most sites, the proportion reached by the SIA ranged from 45.8% in Thiruvananthapuram District to 94.9% in Dibrugarh District. Fewer than 7% of children remained measles zero-dose after the MR SIA (range: 1.1-6.4%) compared to up to 28% before the SIA (range: 7.3-28.1%). DISCUSSION: We demonstrated the MR SIA provided considerable added value in terms of measles vaccination coverage, although there was variability across districts due to differences in routine and SIA coverage, and which children were reached by the SIA. Metrics evaluating the added value of an SIA can help to inform the design of vaccination strategies to better reach zero-dose or undervaccinated children.

Impact and operational feasibility of TrueNat™ MTB/Rif under India's RNTCP.

BACKGROUND: The Revised National Tuberculosis Control Programme (RNTCP) in Andhra Pradesh, India, introduced TrueNat™ MTB/Rif, a rapid molecular test for detecting Mycobacterium tuberculosis (MTB) and rifampicin (RIF) resistance at 193 TB units (TUs) in October 2018. We evaluated its impact on TB diagnosis and assessed the operational feasibility of its deployment at point-of-care (POC) settings. METHODS: We compared the number of presumptive TB cases tested and the number (proportion) of microbiologically positive before (January-August 2018) and after (January-August 2019) the deployment of TrueNat. We interviewed laboratory technicians and Senior TB Laboratory Supervisor from 25 randomly selected TUs to assess operational feasibility. RESULTS: In 2018, 10.5% (range 8.9-13.1) of 245,989 presumptive cases tested were positive. In 2019, of the 185,435 presumptive cases tested, 13.7% (range 9.6-18.9) were positive. The proportion of presumptive TB cases in whom MTB was detected using TrueNat was 14.4% (range 10.0-21.2). TrueNat significantly increased case detection (incidence rate ratio [IRR] 1.30; 95%CI 1.15-1.46), yielding an additional 18 TB cases per 100 000 population. Laboratory technicians became comfortable in performing TrueNat after a median of 10 tests (interquartile range 5-17.5). Invalid reports declined from 6.8% to 3.6%. CONCLUSION: The deployment of TrueNat as POC diagnostic test improved case detection and was operationally feasible under RNTCP.

Hepatitis delta virus infection among the tribes of the Andaman and Nicobar Islands, India.

Hepatitis B virus infection is highly endemic among the tribes of Andaman and Nicobar Islands, India. We screened 223 hepatitis B surface antigen-positive members of these tribes for hepatitis delta virus infection (HDV). The infection was observed only among the Nicobarese. Considering the serious consequences of HDV infection, we suggest that the tribes of these islands should be monitored for HDV infection.

Randomized controlled trial of doxycycline prophylaxis against leptospirosis in an endemic area.

Leptospirosis occurs as seasonal outbreaks, lasting for about 3 weeks during October-November in North Andaman. A randomized controlled trial was undertaken to assess the efficacy of doxycycline prophylaxis in the prevention of infection and clinical disease due to leptospires during the outbreak period. A sample population of 782 persons, randomized into two groups was given doxycycline 200 mg/week and a placebo. The microscopic agglutination test was done on blood samples collected on day zero, after 6 weeks and after 12 weeks. Infection rates and attack rates of clinical illness were calculated in the two groups based on the serological results. Statistically there was no difference in the infection rates among the two groups. However, a statistically significant difference was observed in the clinical disease attack rates (3.11 vs. 6.82%) between study group and control group. The results of the study indicate that doxycycline prophylaxis does not prevent leptospiral infection in an endemic area, but has a significant protective effect in reducing the morbidity and mortality during outbreaks.

Outbreak of leptospirosis with pulmonary involvement in north Andaman.

An outbreak of acute febrile illness with haemorrhagic manifestations and pulmonary involvement occurred in Diglipur of North Andaman during October-November 1993. Investigations were carried out to see whether leptospires were responsible for this outbreak. Serum samples were collected from suspected cases and tested for presence of antibodies to leptospires by microscopic agglutination test (MAT) using a battery of 19 antigens representing 16 serogroups. 66.7 per cent of the specimens showed significant titres of antibodies against leptospires, 18 of 23 paired sera (78.3%) showed sero-conversion or four-fold rise in antibody titres. The commonest serovar involved was Leptospira grippotyphosa followed by L. canicola and L. JEZ bratislava. In 7 patients L. grippotyphosa was the sole serovar against which antibodies were detected. Clinical and epidemiological observations of this outbreak were similar with that of earlier seasonal outbreaks of acute febrile illness with haemorrhagic manifestations occurring in the same area, indicating that the past outbreaks may also have been due to leptospires. This is the first report of pulmonary leptospirosis from India.

Little Andaman Island, a new focus of infection with nocturnally periodic Wuchereria bancrofti.

A filariasis survey was carried out for the first time in the Little Andaman island, covering a population of 12,247 in 12 of the 13 villages. Infection due to Wuchereria bancrofti was found only in 3 villages with microfilaria (mf) rate ranging from 1.02 to 6.45 per cent. Observations on the appearance of mf in peripheral blood showed that the parasite is nocturnally periodic form with a peak at 2000 h. The infection was prevalent only among the settlers from Bihar and Bangladesh and none of the local tribal population was affected. Carriers included 18 males and 4 females. Their age ranged from 6 to 50 yr. Only one of 2788 individuals examined was found to have clinical manifestation. A total of 442 female mosquitoes belonging to eight species were collected and dissected. Natural infection was found only in Culex quinquefasciatus (0.24%). Epidemiological investigations and vector studies indicates local transmission. Thus, this island appears as a new focus of infection.

Prevalence of hepatitis B infection among the primitive tribes of Andaman & Nicobar Islands.

BACKGROUND & OBJECTIVES: Andaman and Nicobar Islands, is the home of six primitive tribes. No information is available on the prevalence of hepatitis B virus (HBV) infection among them. Hence a study was undertaken with the objective of assessing the sero-prevalence of HBV infection among the four accessible tribes of these islands. METHODS: A total of 1266 serum samples were collected from four tribes i.e., Nicobarese, Shompens, Onges and Great Andamanese and tested for the presence of HBsAg and anti-HBs. Information about different risk factors associated with HBV infection was also collected from the Nicobarese tribe. RESULTS: The overall seropositivity rate of HBsAg among the Nicobarese was 23.3 per cent (95% C.I. 21.0-25.9). Hepatitis B was also found to be an important health problem among the Shompens and Onges with HBsAg positivity of 37.8 and 31.0 per cent respectively. The age-wise distribution of these serological markers among Nicobarese tribe indicate that the infection is very common in all the age groups. The sero-prevalence was also found to be very high among the children. CONCLUSIONS & INTERPRETATION: The findings of the present study indicate that hepatitis B infection is hyper endemic among the primitive tribes of these islands. Though none of the risk factors studied in the Nicobarese was found to be significantly associated with HBV infection, the fact that almost 20 per cent of the women in the reproductive age group were positive for HBsAg indicates the possibility of vertical transmission among the Nicobarese. Further studies are required to find out other modes of transmission.

Risk factors in the transmission of leptospiral infection.

An unmatched case control study was conducted to study the various risk factors for acquiring leptospiral infection in Diglipur tehsil of North Andaman. A random sample of 1014 persons residing in various villages of Diglipur was inducted into the study. Serum samples were collected from them and tested for anti-leptospiral antibodies using microscopic agglutination test (MAT) using Leptospira grippotyphosa, L. australis, L. canicola and L. icterohaemorrhagiae antigens. Persons with a titre of 1:50 or more were considered as the cases (550) and the seronegatives as controls (464). Information about 30 variables relating to household characteristics, occupation, contact with animals and behavioural factors was collected by interviewing the subjects. The prevalences of these variables in both the groups were calculated and the odds ratio with 95 per cent confidence intervals were computed. The seroprevalence rate was found to increase linearly with age and it was significantly higher in males. None of the risk factors studied had any association with seropositivity to serovar L. icterohaemorrhagiae. For the other serovars, some form of recent exposure to outdoor environment had significant association. Other factors which had association with infection with specific serovars included use of well or stream water and presence of dogs in the house for infection with L. grippotyphosa, farming families and presence of cattle in the houses for infection with L. australis and the habit of bathing in ponds for infection with L. canicola. These observed associations can be taken as clues of the transmission cycles and would help in guiding further investigations for understanding the epidemiology of leptospirosis in these islands.

Intestinal parasitic infestation among different population groups of Andaman and Nicobar islands.

A survey was carried out among the rural and urban settlers and two tribal groups viz. Nicobarese and Onges, of Andaman and Nicobar islands. The survey covered preschool school aged children and adults. Out of the total 1,384 stool samples examined, 652 (47.1%) showed ova or cysts of one or more intestinal parasites. Among the preschool children, Nicobarese showed the highest overall prevalence rate (80.5%) followed by urban (46.7%) and rural (38.6%) preschool children. Ascaris lumbricoides was the commonest form of parasite encountered in all the groups of preschool children, followed by Trichuris trichura. While ascariasis and trichuriasis were more common among the urban children than in rural children, giardiasis was more common among the rural preschool children. The school age children among rural settlers showed an overall prevalence rate of 61.1% which was significantly higher than that among the rural preschool children. Among the school age children also, ascariasis was the commonest form of parasitosis followed by trichuriasis. The Nicobarese and Onge adults showed significantly higher overall prevalence rates (72.2%) and 71.1% vs 48.6%) compared to rural adults. In all the groups studied ascariasis was the commonest form of parasitosis except in Onges among whom trichuriasis and giardiasis were more common than ascariasis. Change in prevalence rates over age was studied among the rural settlers. While ascariasis and trichuriasis showed peak prevalence rates in school age children prevalence of giardiasis declined with increase in age from a peak in the preschool age group and prevalence rates of hook worm infestation continued increasing beyond school age.

An outbreak of pertussis in Sarli Circle of Kurung-kumey district, Arunachal Pradesh, India.

An outbreak of suspected pertussis occurred in Sarli circle of Kurung-kumey district of Arunachal Pradesh in 2007. We investigated this outbreak to confirm the etiology, estimate the magnitude and identify reasons for its occurrence. Twenty-six deaths were reported from the circle. We identified 72 case-patients meeting the case definition of suspected pertussis. The overall attack rate was 30%. None of the under-five children surveyed had received any vaccine in the past. It is essential to establish facilities for conducting routine immunization in Sarli and organizing special campaign in the area to vaccinate all under-fives with full course of vaccines.

Outbreak of waterborne hepatitis E in Hyderabad, India, 2005.

A large outbreak of hepatitis E occurred in 2005 in Hyderabad, Andhra Pradesh, India. A total of 1611 cases were reported between 1 March and 31 December 2005 (attack rate 40/100,000). The epidemic curve suggested a continuing common source outbreak. Cases were centred around open sewage drains that crossed the old city. The attack rate was significantly higher in neighbourhood blocks supplied by water supply lines that crossed open drains (203/100,000) than in blocks supplied by non-crossing water pipes with a linear trend (38/100 000, P<0.00001). Crossing water pipelines were repaired and the attack rates declined.