The burden of COVID-19 infection in a rural Tamil Nadu community.

BACKGROUND: There have been over 30 million cases of COVID-19 in India and over 430,000 deaths. Transmission rates vary from region to region, and are influenced by many factors including population susceptibility, travel and uptake of preventive measures. To date there have been relatively few studies examining the impact of the pandemic in lower income, rural regions of India. We report on a study examining COVID-19 burden in a rural community in Tamil Nadu. METHODS: The study was undertaken in a population of approximately 130,000 people, served by the Rural Unit of Health and Social Affairs (RUHSA), a community health center of CMC, Vellore. We established and evaluated a COVID-19 PCR-testing programme for symptomatic patients-testing was offered to 350 individuals, and household members of test-positive cases were offered antibody testing. We also undertook two COVID-19 seroprevalence surveys in the same community, amongst 701 randomly-selected individuals. RESULTS: There were 182 positive tests in the symptomatic population (52.0%). Factors associated with test-positivity were older age, male gender, higher socioeconomic status (SES, as determined by occupation, education and housing), a history of diabetes, contact with a confirmed/suspected case and attending a gathering (such as a religious ceremony, festival or extended family gathering). Amongst test-positive cases, 3 (1.6%) died and 16 (8.8%) suffered a severe illness. Amongst 129 household contacts 40 (31.0%) tested positive. The two seroprevalence surveys showed positivity rates of 2.2% (July/Aug 2020) and 22.0% (Nov 2020). 40 tested positive (31.0%, 95% CI: 23.02 - 38.98). Our estimated infection-to-case ratio was 31.7. CONCLUSIONS: A simple approach using community health workers and a community-based testing clinic can readily identify significant numbers of COVID-19 infections in Indian rural population. There appear, however, to be low rates of death and severe illness, although vulnerable groups may be under-represented in our sample. It's vital these lower income, rural populations aren't overlooked in ongoing pandemic monitoring and vaccine roll-out in India.

A science-based response to COVID-19.

The COVID-19 pandemic behaves like many other viruses spread through respiratory routes. This is generally a mild disease for those aged less than 50 years. A complete and prolonged lockdown will reduce COVID-19 mortality but simultaneously lead to a graver public health, social, and economic disaster. The focus has to be based on the reality that exists in an area.

Pilot randomized trial of nutritional supplementation in patients with tuberculosis and HIV-tuberculosis coinfection receiving directly observed short-course chemotherapy for tuberculosis.

OBJECTIVE: To investigate the effects of nutritional supplementation on the outcome and nutritional status of south Indian patients with tuberculosis (TB) with and without human immunodeficiency virus (HIV) coinfection on anti-tuberculous therapy. METHOD: Randomized controlled trial on the effect of a locally prepared cereal-lentil mixture providing 930 kcal and a multivitamin micronutrient supplement during anti-tuberculous therapy in 81 newly diagnosed TB alone and 22 TB-HIV-coinfected patients, among whom 51 received and 52 did not receive the supplement. The primary outcome evaluated at completion of TB therapy was outcome of TB treatment, as classified by the national programme. Secondary outcomes were body composition, compliance and condition on follow-up 1 year after cessation of TB therapy and supplementation. RESULTS: There was no significant difference in TB outcomes at the end of treatment, but HIV-TB coinfected individuals had four times greater odds of poor outcome than those with TB alone. Among patients with TB, 1/35 (2.9%) supplemented and 5/42(12%) of those not supplemented had poor outcomes, while among TB-HIV-coinfected individuals, 4/13 (31%) supplemented and 3/7 (42.8%) non-supplemented patients had poor outcomes at the end of treatment, and the differences were more marked after 1 year of follow-up. Although there was some trend of benefit for both TB alone and TB-HIV coinfection, the results were not statistically significant at the end of TB treatment, possibly because of limited sample size. CONCLUSION: Nutritional supplements in patients are a potentially feasible, low-cost intervention, which could impact patients with TB and TB-HIV. The public health importance of these diseases in resource-limited settings suggests the need for large, multi-centre randomized control trials on nutritional supplementation.

Congenital rubella syndrome and rubella in Vellore, South India.

Rubella, a mild, vaccine-preventable disease, can manifest as congenital rubella syndrome (CRS), a devastating disease of the fetus. To emphasize the inadequacy of the existing rubella vaccination programme in India, we evaluated epidemiological evidence of rubella virus activity with data available from a tertiary-care centre. The proportion of suspected CRS cases that were laboratory confirmed increased from 4% in 2000 to 11% in 2008. During the same period, 329 clinically suspected postnatal rubella cases were tested of which 65 (20%) were laboratory confirmed. Of women (n=770) of childbearing age, 12·5% were susceptible to rubella.

The clinical significance of MIB-1 labeling index in pituitary adenomas.

Pituitary adenomas are unique in several ways--they are rarely malignant and yet can be invasive of several compartments. Recurrences in tumors with bland histological features that have been radically excised are a reason for frustration faced by endocrinologists and neurosurgeons in treatment of pituitary adenomas. Several attempts have therefore been made to determine the growth potential of pituitary adenomas. The aim of the present study was to define the biological significance of the MIB-1 labelling index (MIB-1 LI) in pituitary adenomas. The study included 159 cases of surgically treated pituitary adenoma seen in a single institution. MIB-1 LI was not found to be related to age or gender. The mean MIB-1 LI for clinically functional adenomas was marginally higher than that for clinically non-functional adenomas. There was a significant difference in the MIB-1 LI for tumors with a maximum diameter of more than 4 cm at a MIB-1 LI of ≥2%, however this difference was not statistically significant at a higher MIB-1 LI cut off value of >3%. The mean MIB-1 LI was significantly higher in tumors causing hydrocephalus and in those with cavernous sinus invasion and not when invasion was defined as invasion by tumor in any direction. We conclude that large pituitary macroadenomas, tumors filling the third ventricle causing hydrocephalus and tumors with true cavernous sinus invasions are more likely to have a higher proliferation index. Close follow up of tumors showing these imaging features would be recommended.

Study to Test and Operationalize Preventive Approaches for CKD of Undetermined Etiology in Andhra Pradesh, India.

INTRODUCTION: High prevalence of chronic kidney disease (CKD) not associated with known risk factors has been reported from coastal districts of Andhra Pradesh. The Study to Test and Operationalize Preventive Approaches for Chronic Kidney Disease of Undetermined Etiology in Andhra Pradesh (STOP CKDu AP) aims to ascertain the burden (prevalence and incidence) of CKD, the risk factor profile, and the community perceptions about the disease in the Uddanam area of Andhra Pradesh. METHODS: Study participants will be sampled from the Uddanam area using multistage cluster random sampling. Information will be collected on the demographic profile, occupational history, and presence of conventional as well as nonconventional risk factors. Glomerular filtration rate (GFR) will be estimated using the Chronic Kidney Disease Epidemiology Collaboration equation, and proteinuria will be measured. All abnormal values will be confirmed by repeat testing after 3 months. Cases of CKD not associated with identified etiologies will be identified. Biospecimens will be stored to explore future hypotheses. The entire cohort will be followed up every 6 months to determine the incidence of CKD and to identify risk factors for decline in kidney function. Qualitative studies will be performed to understand the community perceptions and expectations with respect to the interventions. IMPLICATIONS: CKD is an important public health challenge in low- and middle-income countries. This study will establish the prevalence and determine the incidence of CKD not associated with known risk factors in a reported high-burden region, and will provide insights to help design targeted health systems responses. The findings will contribute to the policy development to tackle CKD in the region and will permit international comparisons with other regions with similar high prevalence.

Seroprevalence of Taenia solium antibodies in Vellore district, south India.

Although Taenia solium neurocysticercosis is the cause of almost one-third of epilepsy in Vellore district, south India, the level of exposure to T. solium in the district is not known. This study determined the seroprevalence of cysticercus antibodies in seizure-free, study subjects aged 2-60 years from urban and rural areas of Vellore district. Cysticercus antibodies, as determined by immunoblots, were noted in 15.9% of 1063 people and were significantly higher in the rural population (17.7%) compared with the urban population (6.0%). Twenty-four percent of the rural population and 12% of the urban population ate pork. One-third of all households in the district had one or more members seropositive for cysticercus antibodies. The high index of exposure to T. solium in south India calls for improved animal husbandry and sanitation.

Rates and factors associated with suicide in Kaniyambadi Block, Tamil Nadu, South India, 2000-2002.

BACKGROUND: Inefficient civil registration systems, non-report of deaths, variable standards in certifying death and the legal and social consequences of suicide are major obstacles to investigating suicide in the developing world. OBJECTIVE: The aim of this study was to prospectively determine the suicide rate in Kaniyambadi Block, Tamil Nadu, South India, for the years 2000-2002 using verbal autopsies. METHOD: The setting for the study was a comprehensive community health programme in a development block in rural South India. The main outcome measure was death by suicide, diagnosed by a detailed verbal autopsy and census, and birth and death data to identify the population base. RESULTS: The average suicide rate was 92.1 per 100,000. The ratio of male to female suicides was 1:0.66. The age-specific suicide rate for men increased with age while that for women showed two peaks: 15-24 years and over 65 years of age. Hanging (49%) and poisoning with organo-phosphorus compounds (40.5%) were the commonest methods of committing suicide. Acute and/or chronic stress was elicited for nearly all subjects. More men suffered from chronic stress while more women had acute precipitating events (chi2 = 4.58; p < 0.04). People less than 44 years of age had more acute precipitating events before death while older subjects reported more chronic stress (chi2 = 17.38; p < 0.001). CONCLUSION: The study replicates findings of an earlier study from the area. The suicide rate documented in this study is very high and is a major public health concern. There is a need for sentinel centres in India and in developing countries to monitor trends and to develop innovative strategies to reduce deaths by suicide.

Prevalence and Visual Outcomes of Cataract Surgery in Rural South India: A Cross-Sectional Study.

PURPOSE: To determine the prevalence of cataract surgery and postoperative vision-related outcomes, especially with respect to sex, socioeconomic status (SES) and site of first contact with eye care, in a rural area of South India. METHODS: In a population-based cross-sectional survey of 5530 individuals aged 50 years or older from 10 villages selected by cluster sampling, individuals who had undergone cataract surgery in one or both eyes were identified. Consenting participants were administered a questionnaire, underwent vision assessment and ophthalmic examination. Outcomes were classified as good if visual acuity of the operated eye was 6/18 or better, fair if worse than 6/18 but better than or equal to 6/60, and poor if worse than 6/60. RESULTS: Prevalence of cataract surgery in this age group (771 persons) was 13.9% (95% confidence interval, CI, 13.0-14.9%). In the 1112 eyes of 749 persons studied, at presentation, 53.1% (95% CI 50.1-56.1%) of operated eyes had good, 38.1% (95% CI 35.2-41.0%) had fair, and 8.8% (95% CI 7.1-10.5%) had poor outcomes. With pinhole, 75.2% (95% CI 72.6-77.8%) had good, 17.2% (95% CI 14.9-19.5%) had fair, and 7.4% (95% CI 5.8-9.0%) had poor outcomes. In 76.3% of eyes with fair and poor presenting outcomes we detected an avoidable cause for the suboptimal visual acuity. Place of surgery and duration since surgery of 3 years or more were risk factors for blindness, while SES, sex and site of first eye care contact were not. CONCLUSION: The high prevalence of avoidable causes of visual impairment in this rural setting indicates the scope for preventive strategies.

Rotavirus and other Diarrheal Disease in a Birth Cohort from Southern Indian Community.

OBJECTIVE: To describe the incidence, severity and etiology of diarrheal disease in infants and young children residing in an urban slum community in Southern India. SETTING: Three contiguous urban slums in Vellore, Tamil Nadu. PARTICIPANTS: 452 children participating in a birth cohort study on diarrheal disease; 373 completed three years of follow-up. OUTCOME MEASURES: Diarrheal incidence (obtained by twice-weekly home visits) and severity (assessed by the Vesikari scoring system), and etiological agents associated with diarrhea (through examination of stool specimens by bacteriologic culture, rotavirus enzyme immunoassay, PCR for norovirus and microscopy for parasites). RESULTS: A total of 1856 diarrheal episodes were reported in 373 children. The overall incidence rate of diarrhea was 1.66 episodes per child year for three years, with 2.76 episodes per child year in infancy. The incidence peaked during the months of July and August. Severe diarrhea formed 8% of the total episodes. Rotavirus was the most common pathogen detected, being identified in 18% of episodes. Good hygiene status resulted in 33% protection against moderate-to-severe diarrhea. CONCLUSIONS: This study highlights the burden of diarrheal disease and the important etiological agents of childhood diarrhea in Southern India. Promotion of hygienic behavior through health education may help reduce diarrheal incidence in this and similar communities.

Present status of eye care in India.

India, the second most populous country in the world, is home to 23.5% of the world's blind population. In 1976 India became the first country in the world to start a national program for control of blindness. All surveys in the country have shown that cataract is the most common cause of blindness and all prevention of blindness programs have been "cataract-oriented." However, it has recently been recognized that the visual outcome of the cataract surgeries as well as the training of ophthalmologists has been less than ideal. There is now increasing emphasis on high-quality surgery and up-gradation of skills among ophthalmologists. Other important causes of blindness are refractive errors, childhood blindness, corneal blindness, and glaucoma. The definitions, magnitude, and present status of each of these causes of blindness, as well as efforts at control, are discussed.

Role of frequency doubling perimetry in detecting neuro-ophthalmic visual field defects.

PURPOSE: To report the ability of frequency doubling perimetry to detect "neuro-ophthalmic" field defects, characterize them as hemianopic or quadrantanopic, and differentiate glaucomatous from "other" neuro-ophthalmic field defects. METHODS: Sixty eyes of 30 normal subjects, 50 eyes of 29 patients with glaucomatous defects, and 138 eyes of 103 patients with "typical" neuro-ophthalmic field defects underwent automated perimetry using the Swedish Interactive Threshold Algorithm and frequency doubling perimetry. The sensitivity and specificity for identification of a field defect (frequency doubling perimetry 20-5 and 20-1 screening tests), or to characterize hemianopia/quadrantanopia (full threshold test) were determined. Ability to discriminate glaucomatous defects was determined by comparing frequency doubling perimetry full threshold test in glaucoma to pooled results of normal and neuro-ophthalmic groups. RESULTS: On frequency doubling perimetry, a single point depressed to less than 1% probability had a sensitivity of 97.1% (20-5 test) and 95.7% (20-1 test) for detecting a neuro-ophthalmic visual field defect. The corresponding specificities were 95% using pooled results in normal subjects and patients with glaucoma and "other" neuro-ophthalmic field defects. In 20-5 screening a single abnormal point depressed to less than 2% probability level had a sensitivity of 98.6% (specificity 85%). Two abnormal points in the 20-1 screening depressed to less than 1% probability level had a specificity of 100% (sensitivity 84.8%). In frequency doubling perimetry full threshold, sensitivity and specificity for detection of hemianopia were 86.8% and 83.2%; for quadrantanopia they were 79.2% and 38.6%. The sensitivity and specificity for categorizing a defect as glaucomatous were 86% and 74.7%. CONCLUSIONS: Frequency doubling perimetry is a sensitive and specific test for detecting "neuro-ophthalmic" field defects. The presence of two abnormal points (20-1 screening program) "rules in" the presence of a field defect. A normal 20-5 program (absence of a single abnormal point) almost "rules out" a defect. Frequency doubling perimetry could not accurately categorize hemianopic, quadrantanopic, or glaucomatous defects.

Five year risk of progression of primary angle closure suspects to primary angle closure: a population based study.

AIM: To report progression of primary angle closure suspects (PACS) to primary angle closure (PAC) at the 5 year follow up of a population based sample. METHODS: 82 of 118 PACS who could be contacted and 110 randomly selected normals from a population based survey in 1995 were invited for a follow up examination in 2000. Progression to PAC was based on the development of raised IOP or synechiae in a PACS. RESULTS: 50 of the 82 PACS contacted were examined. 11 (22%; 95% CI 9.8 to 34.2) developed PAC (seven synechial and four appositional); all were bilateral PACS. Two of 50 people previously diagnosed as PACS were reclassified as normal. One person among the 110 normals progressed to PAC. The relative risk of progression among PACS was 24 (95% CI 3.2 to 182.4). There was no significant difference in axial length, anterior chamber depth, or lens thickness between those who progressed and those who did not. None of the patients developed optic disc or field damage attributable to angle closure. One angle closure suspect was diagnosed to have normotensive glaucoma. CONCLUSION: In this population based study of PACS the 5 year incidence of PAC was 22%; none developed functional damage. Bilateral PACS was a clinical risk factor for progression.

Optic disc morphology in south India: the Vellore Eye Study.

AIM: To evaluate the morphology of the optic nerve head in an unselected population group in south India. METHODS: The study included 70 subjects forming a population based sample, selected in a random manner. Mean age was 47.5 (SD 8.7) years, mean refractive error measured -0.07 (1.11) dioptres (range -4.50 to +2.50 dioptres). Optic disc slides were morphometrically analysed. RESULTS: Mean optic disc area measured 2.58 (0.65) mm(2). It was statistically independent of age and refractive error. Optic disc shape was slightly vertically oval. Mean neuroretinal rim area was 1.60 (0.37) mm(2). It was significantly and positively correlated with optic disc size and optic cup size. It was independent of age, sex, refractive error, and axial length. In all subjects included in the study, the rim was smallest in the temporal horizontal optic disc sector. Mean horizontal cup/disc diameter ratio (0.66 (0.07)) was significantly (p<0.001) higher than the mean vertical cup/disc diameter ratio (0.56 (0.08)). Both ratios were highly significantly (p <0.001) and positively correlated with optic disc size. The alpha zone of parapapillary atrophy (0.84 (0.29) mm(2)), and beta zone (0.13 (0.38) mm(2)), respectively, occurred in 69 (98.6%) subjects and in eight (11.4%) subjects, respectively. They were significantly larger in the temporal horizontal sector. The alpha zone was significantly (p<0.001) larger and occurred significantly more often than beta zone. Retinal arterioles and venules were wider, and in spatial correlation, the visibility of the retinal nerve fibre layer was significantly better, in the temporal inferior disc arcade and the temporal superior arcade than in the nasal superior arcade and the nasal inferior vessel arcade. Except for the absolute size measurements these optic nerve head parameters did not differ markedly (p >0.05) from the values found in white people. CONCLUSIONS: South Indians and white people do not show marked differences in the morphology of the optic nerve head as measured by morphometric optic disc parameters, with the possible exception of the absolute optic disc dimensions.

Use of pattern standard deviation instead of corrected pattern standard deviation in Anderson's criteria.

PURPOSE: To determine whether the use of pattern standard deviation instead of corrected pattern standard deviation, as part of Anderson's criteria, makes a difference in categorizing a single field printout using the full threshold strategy on the Humphrey's Field Analyzer. MATERIALS AND METHODS: Forty-eight patients with glaucomatous field defects of varying severity underwent full threshold perimetry on the Humphrey's Field Analyzer. The third field of one eye was used for the study. The agreement between CPSD and PSD alone was determined. Each field was then categorized using Anderson's criteria first using CPSD and then PSD. The kappa statistic was used to determine agreement in both situations. RESULTS: The agreement between CPSD and PSD alone, as determined by kappa, was 0.77. The kappa statistic for categorization using Anderson's criteria was 0.82; the weighted kappa was 0.92. CONCLUSION: There was almost perfect agreement using the PSD instead of CPSD as part of Anderson's criteria. This substitution seems valid for the spectrum of field defects used in this series, at least for the full threshold programs.

Brightness discrimination test is not useful in screening for open angle glaucoma.

PURPOSE: Brightness discrimination test (BDT) is routinely employed to assess asymmetrical optic nerve dysfunction and has been suggested as a screening test for primary open angle glaucoma (POAG). We tested the reliability and validity of BDT in the diagnosis of POAG. METHODS: The study groups included 34 patients with established primary open angle glaucoma, 20 glaucoma suspects, and 33 age-sex matched controls. Cataract was not an exclusion criterion in these groups. The normal brightness score was determined to be 88% (mean score, 94%-2 SD) in a pilot study. Brightness discrimination test was performed in all subjects by two observers independently. BDT showed an excellent interobserver agreement (weighted Kappa 0.84). RESULTS: The presence of a cataract alone increased the risk of brightness impairment twofold, glaucoma alone increased the risk eightfold, and the presence of both conditions by 17 times compared to those with neither condition. BDT was not a useful test in the diagnosis of POAG (sensitivity 67% and specificity 93%); the ability to detect a significant field defect was also poor (sensitivity 53% and specificity 76%). CONCLUSIONS: There was poor association between decreased brightness scores and asymmetrical field defects as determined by the Humphrey's field analyzer (HFA).

Frequency doubling perimetry in glaucoma.

PURPOSE: To evaluate the validity of frequency doubling perimetry (FDP) in the detection of glaucomatous field defects. METHODS: Group I consisted of 85 eyes of 85 patients with established field defects in automated perimetry, classified by severity of defect. Group II consisted of 48 eyes of 48 control subjects. Both groups underwent Swedish Interactive Testing Algorithm (SITA) standard tests as well as FDP screening strategies (C20-1 and C20-5 and full threshold test). Sensitivity and specificity measures for the FDP tests were calculated using one new and two previously published algorithms. RESULTS: A described scoring system provided the best sensitivity (85.9%) and specificity (95.1%). For moderate and severe cases, the sensitivity improved to 91%. Quantification of the defect did not improve detection. CONCLUSIONS: FDP is a valid screening test for glaucoma. The scoring system described by Patel et al. provided the best results.

Risk of relapse among non-lepromatous patients released from treatment after dapsone monotherapy.

Information on 14,625 non-lepromatous patients released from treatment after dapsone monotherapy and followed up to a maximum of 15 years at the ILEP project. Dharmapuri, India, was analysed to study the pattern of relapses. The overall relapse rate was 5/1000 person years. Males had a higher relapse rate than females. The risk of relapse increased with age, number of lesions and duration of treatment. The risk for relapse remained constant over several years after release from treatment. Even though the absolute risk for relapse after MDT may be different, the pattern of relapses and the factors affecting it may be similar to what has been shown in this study.

The role of intrahousehold contact in the transmission of leprosy.

This study examines the role of intrahousehold contact in the transmission of leprosy using the case control methodology. The study was done in the leprosy control area of the Community Health and Development (CHAD) Programme of the Christian Medical College. Three age, sex and village matched controls were selected for each case. This study shows that persons with intrahousehold contact with leprosy have a higher risk of acquiring leprosy compared with those who did not (RR 2.509; 95% confidence limits 1.23-5.109).

Trends of smoking among medical students.

The overall smoking prevalence among male medical students between the years 1955 and 1988 in a medical college in South India was 39.51 per cent. The trends of smoking appeared to be in three phases. An initial phase comprising of a steady rise to a peak in the late sixties and seventies, followed by a plateau of the prevalence in the next ten years and ultimately a sharp fall in the last five years. Study based on a mailed-in questionnaire to ten batches of students selected randomly, to study the factors affecting initiation and quitting of smoking showed that the peak period of initiation seemed to be in the two years before and after joining the course. There was a significant relationship between the presence of a smoker in the family and picking up the habit. Conversely, no significant relationships were found with respect to quitting.