Objective: On 25 July 2022, trainees from the Field Epidemiology Training Programme in Northern Luzon, Philippines were sent to conduct an epidemiological investigation of six confirmed cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among staff of a regional hospital in Mountain Province. The investigation had three objectives: to profile the cases, identify the source and mode of transmission, and recommend prevention and control measures. Methods: Descriptive epidemiology was used to investigate the outbreak, with the standard case definition issued by the Philippine Department of Health. Results: A total of 167 hospital personnel and interns tested positive for SARS-CoV-2 infection between 6 July and 31 August 2022, with a peak in the number of cases on 20 July. Among the cases, 57 (34%) had a history of travel, with 41 (25%) having travelled to Boracay island to attend team-building activities. Most cases were asymptomatic, and the most affected group was those aged 30–34 years. The highest number of cases occurred among nurses. It was discovered that the team-building activities on Boracay did not strictly adhere to safety protocols. Discussion: This outbreak suggests that transmission of SARS-CoV-2 among health-care workers can occur through contact with other staff members outside of the hospital setting and highlights the importance of strict adherence to safety protocols to prevent the spread of SARS-CoV-2.

Problem: As of 2022, only 49 graduates of the Philippines’ Field Epidemiology Training Programme (FETP) were employed by the Philippine Government, emphasizing the urgent need to increase the number of practicing field epidemiologists to better equip the country for public health emergencies. Context: The FETP–Intermediate Course (IC) curriculum is based mainly on the module of the United States Centers for Disease Control and Prevention that was incorporated into the Philippine context. It consists of five 1–2-week lecture series that provide participants with the knowledge and tools necessary to conduct job-relevant field projects. Individual projects are the centrepiece of the FETP–IC ,requiring trainees to investigate outbreaks, design and develop protocols, conduct field data collection, manage data, analyse data, interpret data, write reports and deliver oral presentations. Action: To address the shortage of practicing field epidemiologists in the Philippines, a subnational initiative in Northern Luzon was implemented. Outcome: Within 3 years, the two FETP–IC subnational training programmes have produced 42 applied epidemiologists who will strengthen epidemiology and surveillance in their respective localities. As of February 2023, 92 studies have been conducted, including 39 outbreak investigations, 37 data quality analysis/process improvement projects, 10 epidemiological studies and six surveillance evaluations. Discussion: By training and deploying skilled epidemiologists to local health offices and hospitals, the programme is helping to improve the capacity of the health system to respond to public health threats and protect the health of the population. The programme’s emphasis on practical training and real-world experience is an effective way to build a strong and sustainable epidemiological workforce.

On 12 September 2022, a 10-year-old female in Paracelis municipality, Mountain Province, the Philippines, without travel history outside the municipality, experienced acute onset of fever and a change in mental status with disorientation, an altered level of consciousness and new onset of seizures. She was hospitalized at the district hospital from 1 to 3 October 2022, before being transferred to the regional hospital. As diphtheria was originally suspected, the investigation team reviewed records and reports and interviewed key informants to gather additional information and organize case finding and contact tracing. The patient’s condition was laboratory-confirmed for Japanese encephalitis virus infection. An environmental survey was carried out at the patient's residence to check for the presence of vectors and contributing factors. Exemplifying inadequate vaccination coverage for Japanese encephalitis virus in Mountain Province, the patient had not been vaccinated against the disease. It is recommended that vaccination campaigns be immediately implemented in the affected area and the surveillance system be strengthened for early detection and prompt response to the emergence of cases and outbreaks. Overall, the investigation highlighted the importance of strong surveillance and response systems for early detection and control of diseases, such as Japanese encephalitis virus. It also underscores the need for comprehensive vaccination programmes to prevent outbreaks and protect vulnerable populations.

Objective: On 24 September 2022, the Regional Public Health Unit in Ilocos received a report of a cluster of suspected hand, foot and mouth disease (HFMD) in one school in Balungao, Pangasinan Province, the Philippines. On 4 October 2022, the public health unit sent a team from the Field Epidemiology Training Program – Intermediate Course to conduct an outbreak investigation. Methods: Active case-finding was conducted at the school. A suspected case was defined as any student or staff member with mouth ulcers and papulovesicular or maculopapular rash on the palms, fingers, soles of the feet or buttocks occurring from 1 September to 5 October 2022. We interviewed school officials about possible sources of infection and students’ activities. We collected oropharyngeal swab samples for testing. Findings were used for descriptive analysis. Results: Nine suspected cases of HFMD were detected, with the highest number of cases (6, 67%) occurring in children in grade 1. The majority of cases (7, 78%) were 6 years old, and five cases (56%) were male. Seven (78%) of the cases had been exposed to a confirmed case of HFMD, as reported by their parents or guardians and teachers. Six cases (67%) were positive for coxsackievirus A16 and two (22%) for enterovirus. Discussion: The causative agents of this outbreak were coxsackievirus A16 and other enteroviruses. Direct contact with a confirmed case was the source of transmission, with a lack of physical distancing in classrooms likely contributing to transmission. We recommended that the local government implement measures to control the outbreak.