COVID-19 Epidemiologic Investigations

Figure 1

Figure 1. Distribution of India Field Epidemiology Training Program officers (advanced and intermediate current officers and alumni) during COVID-19 response, India, March 2020–June 2021. Circle sizes indicate number of officers.

During March 2020–June 2021, a total of 50 FETP officers (26 officers from AEP and 24 officers from EIS) participated in >44 COVID-19 response projects across India. The 24 EIS officers, 26 AEP officers, and 73 FETP alumni were distributed throughout the country as of June 2021 (Figure 1). EIS officers and FETP alumni were working in 22 (61%) of the 37 states and union territories; the largest concentration of EIS officers and FETP alumni was in New Delhi. As part of the COVID-19 response, broad areas of support from FETP officers to local and state public health authorities were surveillance data analysis and surveillance system strengthening, cluster outbreak investigations in the community and institutional settings such as residential and healthcare centers, epidemiologic studies, and developing and implementing assessment tools for infection mitigation (Table 1). Select FETP officer epidemiologic investigations and their successes are discussed next.

Involvement of the India FETP in India’s COVID-19 response began in March 2020 with reporting of initial COVID-19 cases. When India reported its first cluster of COVID-19 in March 2020 in a city in northern India, NCDC deployed EIS officers to develop a containment plan and establish influenza-like illness (ILI) surveillance in the community. Reverse transcription PCR (RT-PCR) testing of potential cases was conducted alongside contact tracing. Using case mapping, 3 containment zones were identified, and >1,700 field teams conducted a door-to-door survey of ILI cases. Over the course of 17 days, 3,561 ILI cases were identified. Of these, 8 cases were laboratory confirmed as COVID-19; of those cases, 3 (38%) case-patients had a history of recent travel outside India, 4 (50%) were in direct contact with a person confirmed to have COVID-19, and 1 (13%) was an indirect contact of a confirmed COVID-19 case-patient (second-generation case). Officers implemented a COVID-19 cluster containment plan that included enhanced surveillance around identified clusters and contact tracing using rapid response teams. The plan was successful in preventing case transmission beyond the second generation.

In March 2020, a COVID-19 cluster was reported among healthcare workers in a cancer hospital in northern India. In the early days of the pandemic, healthcare facilities did not have COVID-19–specific protocols for source reduction. EIS officers led an investigation to identify potential factors associated with these infections and recommended steps to prevent further transmission. Testing and contact tracing identified 25 case-patients, of which 18 (72%) persons were involved in aerosol-generating procedures without following precautions against airborne transmission. Support from FETP officers led to the development of infection prevention and control checklists for healthcare settings and, during the course of the pandemic, served as a successful strategy for ongoing cluster containment activities nationwide. (7).

Figure 2

Figure 2. COVID-19 cases in a coastal fishing community in southern India, June–July 2020.

In June 2020, a coastal community in the southern part of India reported 620 COVID-19 cases. An investigation led by an EIS officer was initiated to identify potential risk factors associated with this cluster. A 1:2 case–control study was conducted at the community health center level. A case-patient was defined as a resident of the identified locality who tested positive for COVID-19 during June 17–July 25, 2020. Cases started rising in the first week and peaked in the second week of July (Figure 2). This case–control study demonstrated that 31% (15/49) of case-patients had exposure to the local fish market compared with 10% (9/93) of controls (odds ratio [OR] 3.9, 95% CI 1.4–11), and 37% (18/49) of case-patients had a family member in the fish business compared with 16% (15/93) of controls (OR 2.8, 95% CI 1.2–6.7). These findings underpin the need for adherence to physical distancing to minimize contact with infected persons and the benefit of wearing a face covering or mask.

On March 30, 2021, a COVID-19 outbreak was reported in a residential training institute in the northeastern part of India. Students at the institute came from across India. The infections began after the reopening of training sessions after the lockdown was lifted in February 2021. An AEP officer investigated the outbreak and recommended containment measures. A total of 114 COVID-19–positive case-patients (111 confirmed through RT-PCR) were identified (attack rate 99%). The median patient age was 24 years (range 1–78 years), and 27 (24%) were symptomatic. Of the 114 case-patients, 98 (86%) were students; the remainder were faculty and staff. The investigation led to the closing of the school and implementation of school infection control assessment tool (8).

Operational Support Activities

Figure 3

Figure 3. Implementation changes in surveillance activities in Udupi, Karnataka, India, 2020–2021. EIS, Epidemic Intelligence Service.

India FETP officers supported district administrations in strengthening local level surveillance systems, which helped authorities closely monitor COVID-19 activity and the delivery of supplies. An EIS officer was appointed as the nodal officer for COVID-19 containment by the district administration of Udupi, a district in southern India. This officer received the mandate to establish a new surveillance system across the district to guide containment efforts. Early in the pandemic, the officer helped the district transition from paper-based forms to digital surveillance using the EpiCollect5 application (https://five.epicollect.net), a free and easy-to-use mobile data-gathering platform. The application proved especially useful in helping to trace returnees from abroad. The new surveillance system used a virtual platform for trainings, meetings, and discussions. With the help of information gathered through the early transition to digital surveillance, revised guidelines were disseminated and implemented in the district within 2 days (rather than months) of their update. This pace has been maintained throughout the pandemic. The local EIS officer in Udupi in the state of Karnataka played a crucial role in implementing changes in surveillance activities in the district (Figure 3)

During the second wave of COVID-19 in India in April 2021, the district of Udupi observed a 100% increase in cases, which stretched healthcare infrastructure and led to a shortage of consumables such as oxygen and diagnostic supplies. An EIS officer appointed as the nodal officer for COVID-19 containment in the district was assigned to assess oxygen consumption. The officer’s analysis revealed that ≈17% (120/750) of hospitalized patients needed ventilatory or high-flow oxygen support during the peak of the outbreak. Because of patient compliance and ease of use, physicians initially preferred high-flow nasal oxygen cannulas for treatment. These continuously use oxygen at the same flow rate during inspiration and expiration, which results in waste. Unlike high-flow nasal oxygen, ventilators or nonrebreathing masks use oxygen only during inspiration, which has been shown to reduce oxygen consumption by 25%–30%. Along with this intervention, an EIS-led team audited oxygen demand in the district hospitals, which calibrated oxygen administration to maintain blood oxygen saturation of 90%–95%. This exercise reduced oxygen requirement by 8%–10%. Under the officer’s supervision, a detailed oxygen delivery pipeline inspection was conducted in major hospitals to find and correct leakage points, saving another 5% of oxygen.

Kumbh Mela, a mass religious gathering that occurs once every 12 years, brings pilgrims from all parts of India and other countries to Haridwar, Uttarakhand. The Kumbh Mela in 2021 was scheduled to take place within a 12.3 km² area during the months of March and April 2021. More than 10 million pilgrims were expected to participate in this religious gathering, essentially doubling the state population over a period of 1 month. The state government provided guidance to attendees on recommended COVID-19–appropriate behaviors, including mask-wearing. WHO and NCDC EIS and AEP officers participated in public health response activities in addition to regular disease surveillance and preparedness duties. FETP officers assessed mask-wearing compliance among Kumbh Mela attendees in Haridwar (6,200 persons observed in 3 weeks) and provided daily updates on COVID-19–appropriate behavior to the administration. Those updates were then used to plan corrective measures. They also assessed acceptance of the COVID-19 vaccine among Kumbh Mela pilgrims >18 years of age and determined factors associated with vaccine hesitancy. Among the interviewed pilgrims, 44% (140/318) had received >1 dose of COVID-19 vaccine, and among the 56% (178/318) unvaccinated persons, 63.0% (112/178) were not eligible for vaccination (persons <45 years of age were not eligible for vaccination in March–April 2021).

Policy and Global Health Implications

Many of the COVID-19 cluster investigations and operational support activities undertaken by India FETP officers had policy implications at the state and national level (Table 2). These implications included standardizing infection prevention and control practices in healthcare settings and schools and establishing robust surveillance systems in select districts (7,8).

The COVID-19 pandemic has highlighted the contribution of trained field epidemiologists in a public health emergency and recognized them as an integral part of the public health workforce on the frontline. Most currently enrolled and alumni FETP officers supported COVID-19 pandemic response work at their respective duty stations. The remainder mentored current FETP officers in investigative and containment activities. The importance of a strong network of trained field epidemiologists is now well accepted at the highest level in the government. A Parliamentary Standing Committee review report on COVID-19 response has recognized the crucial gap of epidemiologists in India’s public health system (9). The committee also observed that, per the Workforce Development Action Package under the Global Health Security Agenda, the country needs to work toward achieving the target of 1 trained field epidemiologist per 200,000 population (10,11).

Although the pandemic has provided insights into strengthening the public health workforce on the frontline (epidemiologists and surveillance officers), it has also pushed the FETP program to become more innovative in curriculum delivery. Officers from all 3 hubs are spread across the country, but the FETP struggled to provide in-person training opportunities for officers because of travel restrictions, which delayed the completion of some core learning activities. However, because the FETP officers were part of the public health system, they received multiple opportunities both through the FETP and their placement sites to participate in COVID-19 response efforts. At each hub, the FETP adopted innovative hybrid instructional and mentoring methods using online platforms such as Zoom Video Communication (https://zoom.us) for induction trainings and remote mentoring sessions to provide learning opportunities for officers.

In addition to highlighting opportunities to modernize curriculum delivery, the pandemic also raised awareness regarding the inequitable distribution of trained public health workers within India. Such inequities in remote rural areas are difficult to address because current public health services are already constrained. This challenge could be managed through training models with an information technology–based learning management system, hybrid models of training, flexible options for placement, and on-site one-to-one mentoring opportunities. The FETP in India is exploring options to develop system tools to optimize learning and training management.