Retaining Patients with Drug-Resistant Tuberculosis on Treatment During the COVID-19 Pandemic - Dharavi, Mumbai, India, 2020-2022.

Mumbai, India's second largest city, has one of the highest prevalences of drug-resistant tuberculosis* (DRTB) in the world. Treatment for DRTB takes longer and is more complicated than treatment for drug-susceptible tuberculosis (TB). Approximately 300 persons receive a new DRTB diagnosis each year in Mumbai's Dharavi slum†; historically, fewer than one half of these patients complete DRTB treatment. As nationwide restrictions to mitigate the COVID-19 pandemic were implemented, a program to facilitate uninterrupted DRTB care for patients receiving treatment was also implemented. A comprehensive tool and risk assessment provided support to DRTB patients and linked those who relocated outside of Dharavi during the pandemic to DRTB care at their destination. During May 2020-September 2022, a total of 973 persons received DRTB treatment in Dharavi, including 255 (26%) who relocated during treatment. Overall, 25 (3%) DRTB patients were lost to follow-up, a rate substantially lower than the rate before the pandemic (18%). Proactive planning and implementation of simple tools retained patients on treatment during periods of travel restrictions and relocations, improving programmatic outcomes. This approach might aid public health programs serving migrant populations or patients receiving treatment for DRTB during public health emergencies.

Impact of COVID-19 vaccination on transmission risk of breakthrough infections: Lessons from adapted N95 mask sampling for emerging variants and interventions.

This study used an adapted N95 mask sampling to understand the effect of COVID-19 vaccination in the context of circulating variants on infected individuals to emit the virus into the air, a key risk factor of transmission. Mask, swab, and blood samples were collected from 92 COVID-19 patients vaccinated (Covishield/COVAXIN-partial/fully) or unvaccinated between July and September 2021 during the Delta-dominated period in Mumbai. Mask/swab samples were analyzed by reverse transcription polymerase chain reaction for viral RNA. Blood was evaluated for SARS-CoV-2 anti-spike and nucleocapsid antibody responses. At <48 h of diagnosis, 93% of the patients emitted detectable viral RNA, with 40% emitting >1000 copies in 30 min (high emitters). About 8% continued to be high emitters even after 8 days of symptom onset. No significant difference was observed in emission patterns between partial, full, and unvaccinated patients. However, when vaccinated patients were stratified based on spike protein neutralization and nucleocapsid immunoglobulin G (IgG), the group with moderate/high neutralization showed a significantly lower proportion of high emitters and viral RNA copies than the group with no/low neutralization, which further reduced in the group having antinucleocapsid IgG. In conclusion, mask sampling showed that Delta infections were associated with greater virus emission in patients, which was significantly reduced only in vaccinated patients with moderate/high SARS-CoV-2 neutralization, especially with evidence of past infection. The study demonstrated that mask sampling could be useful for understanding the transmission risk of emerging variants, screening vaccine/booster candidates, and guiding control interventions.

Genomics of postvaccination SARS-CoV-2 infections during the Delta dominated second wave of COVID-19 pandemic, from Mumbai Metropolitan Region (MMR), India.

The present study was initiated to understand the proportion of predominant variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in postvaccination infections during the Delta dominated second wave of coronavirus disease 2019 (COVID-19) in the Mumbai Metropolitan Region (MMR) in India and to understand any mutations selected in the postvaccination infections or showing association with any patient demographics. Samples were collected (n = 166) from severe/moderate/mild COVID-19 patients who were either vaccinated (COVISHIELD/COVAXIN-partial/fully vaccinated) or unvaccinated, from a city hospital and from home isolation patients in MMR. A total of 150 viral genomes were sequenced by Oxford Nanopore sequencing and the data of 136 viral genomes were analyzed for clade/lineage and for identifying mutations. The sequences belonged to three clades (21A, 21I, and 21J) and their lineage was identified as either Delta (B.1.617.2) or Delta+ (B.1.617.2 + K417N) or sub-lineages of Delta variant (AY.120/AY.38/AY.99). A total of 620 mutations were identified of which 10 mutations showed an increase in trend with time (May-October 2021). Associations of six mutations (two in spike, three in orf1a, and one in nucleocapsid) were shown with milder forms of the disease and one mutation (in orf1a) with partial vaccination status. The results indicate a trend toward reduction in disease severity as the wave progressed.

COVID-19 Serological Survey-3 Prior to Second Wave in Mumbai, India.

Background: Subsequent to serosurveys 1 and 2 for COVID-19 carried out in three wards of Mumbai in July and August 2020, Municipal Corporation of Greater Mumbai conducted serosurvey 3 in March 2021. This was to identify the extent of exposure by testing specific IgG antibodies against COVID-19. Material and Methods: A cross-sectional study was conducted to find the prevalence of seropositivity in Mumbai, which included 10,197 samples belonging to patients visiting public dispensaries (slum population, 6006) and private (nonslum population, 4191) laboratories of Aapli Chikitsa network for blood investigations for non-COVID illnesses. The ward-wise number of unlinked anonymous samples from 24 wards was predecided by using probability proportionate sampling. The samples were collected using quota sampling technique as per predecided sample for each ward. These samples collected from nonimmunized individuals were tested for IgG antibodies at the Molecular Biology Laboratory of Kasturba Hospital for Infectious Diseases by chemiluminescence assay (CLIA) method. Results: The overall seropositivity was found to be 36.3% (41.6% in slum and 28.59% in nonslum population). It was more in city wards (38.28%) followed by western suburb (36.47%) and then eastern suburb wards (34.86%), matching with the proportion of cases in these wards during the study period. There was no significant difference in seropositivity among males and females and in different age groups. Conclusions: Seropositivity is higher in slum areas than nonslum areas. It has reduced in slum areas and increased in nonslum areas as compared to findings of serosurveys 1 and 2. This explains the detection of a greater number of cases from nonslum areas in the second wave. The average seropositivity of 36.3% justifies the necessity of immunization on a wider scale in the city. Periodic serosurveys are required at fixed intervals to monitor the trend of infection and level of herd immunity.

Epidemiological study to assess the impact of COVID-19 pandemic on the occurrence of monsoon-related diseases in the city of Mumbai.

BACKGROUND: The onset of monsoons in Mumbai poses an additional health disease burden in the form of rising vector-borne and water-borne diseases such as dengue, malaria, leptospirosis, hepatitis, typhoid, chikungunya, and acute gastroenteritis. These monsoon-related illnesses are preventable with hygienic and sanitation measures that are likely to have been adopted during COVID-19 pandemic. AIM: To assess the impact of COVID-19 pandemic on the occurrence of monsoon-related diseases in the city of Mumbai and find out determinants of variations if any. MATERIAL AND METHODS: This was a retrospective descriptive study. Universal sampling was done using secondary data collected from the Epidemiological Cell of Municipal Corporation of Greater Mumbai (MCGM). Data mining was performed to obtain the trends of the monsoon-related diseases in Mumbai. RESULTS: COVID-19 pandemic has remarkably affected the city of Mumbai with approximately 3 lakh cases till December 2020. MCGM has taken a lot of efforts resulting in a recovery rate of close to 95% with less than 3% mortality. With the effective use of social behavior change communication, which focused on masks, frequent hand washing, and social distancing, there seems to be a decline in monsoon-related illnesses in the year 2020 as compared to the previous two years of 2018 and 2019. CONCLUSION: Monsoon-related illnesses are impacted by behavior and lifestyle modifications like hygiene and environmental sanitation practiced during the COVID-19 pandemic. This study highlights the importance of these universal hygienic practices and their utility in the long-term reduction of monsoon-related illnesses.

Community transmission of SARS-CoV-2 with B.1.1.7 lineage in Mumbai, India.

The B.1.1.7 (Alpha) variant has been detected in Mumbai, India during February 2021. Subsequently, we retrieved 43 sequences from specimens of 51 COVID-19 cases from Mumbai. The sequence analysis revealed that the cases were mainly affected with Alpha variant which suggests its role in community transmission of SARS-CoV-2 in Mumbai, India.

Interventions to respond to COVID 19 pandemic in Mumbai and way forward.

With the emergence of COVID 19 pandemic, the approach used by Municipal Corporation of Greater Mumbai (MCGM) was based on all guidelines of COVID 19 prepared by Ministry of Health and Family Welfare (MoHFW). However, Mumbai undertook a special innovate model used in the mission Mumbai - Dharavi for COVID 19. Additionally, MCGM undertook a proactive approach of "chasing the virus" with its 4Ts: 1. Tracing 2. Tracking 3. Testing 4. Treating in high-risk slum clusters and it reflects the result of declining the incidence and case fatality due to COVID 19. Establishing public health surge capacities which include active surveillance, contact-tracing and follow-up besides early detection, isolation and management of cases are important steps for fighting the COVID 19 pandemic. Collaborating with all partners and setting up a Task force for establishing clinical management protocols was unmissable.