ReliefWeb

AUTHORS

Mariko Saito-Obata, Mayuko Saito, Titus Tan, Inez Andrea P. Medado, Clyde Dapat, Michiko Okamoto, Raita Tamaki, Rowena C. Capistrano, Edelwisa Segubre-Mercado, Socorro P. Lupisan, Hitoshi Oshitani

ABSTRACT

Introduction: Typhoon Yolanda (Haiyan) hit the central part of the Philippines on November 8, 2013. To identify possible outbreaks of communicable diseases after the typhoon, nasopharyngeal swabs, stool and blood samples were collected from patients who visited the Eastern Visayas Regional Medical Center due to acute respiratory infection (ARI), acute gastroenteritis (AGE) or other febrile illness (OFI) including suspected dengue fever, between November 28, 2013 and February 5, 2014.

Methods: Samples were tested on-site for selected pathogens using rapid diagnostic tests. Confirmation and further analysis were conducted at the Research Institute for Tropical Medicine (RITM) in Manila using polymerase chain reaction (PCR) and sequencing. Residues of the rapid diagnostic tests and samples collected in the filter papers (FTATM card) were transported to Manila under suboptimal conditions. PCR results were compared between the kit residues and the filter papers.

Results: A total of 185 samples were collected. Of these, 128 cases were ARI, 17 cases were AGE and 40 cases were OFI. For nasopharyngeal swab samples, detection rates for enterovirus and rhinovirus residues were higher than the filter papers. For stool samples, rotavirus positive rate for the filter paper was higher than the kit residues. We also managed to obtain the sequence data from some of the kit residues and filter papers.

Discussion: Our results confirmed the importance of PCR for the laboratory diagnosis of infectious diseases in post-disaster situations when diagnostic options are limited.

FUNDING STATEMENT

This study was supported by the Japan Initiative for Global Research Network on Infectious Diseases (J-GRID) from the Japan Agency for Medical and Research and Development (AMED), the Grant-in-Aid for Scientific Research (A) from the Japan Society for the Promotion of Science (JSPS), the Science and Technology Research Partnership for Sustainable Development (SATREPS) from AMED and Japan International Cooperation Agency (JICA). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

INTRODUCTION

Typhoon Yolanda (Haiyan) hit the central part of the Philippines on November 8, 2013, ­­which caused devastating damages including 6,300 reported deaths and 1,062 people missing1. After major disasters, outbreaks of communicable diseases may occur due to poor sanitation and crowded conditions 2,3. Furthermore, the risk of communicable disease outbreak is often exaggerated. Therefore, it is important to monitor if there are any outbreaks in affected areas after a disaster. However, laboratory confirmation is usually not available due to lack of electricity, necessary laboratory materials, and system for transporting samples. To date, there are no general guidelines for laboratory testing in post-disaster settings. Thus, in this study, we conducted laboratory diagnosis of communicable diseases after a strong typhoon, where cold chain was not available.

The Tohoku University of Japan and the Research Institute for Tropical Medicine (RITM) of the Philippines established the RITM-Tohoku Collaborating Research Center on Emerging and Re-emerging Infectious Diseases. The center has been conducting researches on childhood pneumonia, influenza-like illness and acute gastroenteritis in Tacloban City and surrounding areas since 2008 (Figure 1) 4,5. The research laboratory that had been established inside the Eastern Visayas Regional Medical Center (EVRMC) compound was totally damaged during the typhoon (Figure 2). We provided laboratory support to conduct laboratory diagnosis for samples collected from patients who visited EVRMC after the typhoon. Various rapid test kits that were selected based on our research data and past surveillance information in the area were provided for on-site diagnosis6,7. In addition, to detect possible outbreaks and other pathogens that were outside the scope of rapid test kits, samples were collected in FTATM cards (GE Healthcare Lifesciences), which is a commercially available filter paper treated chemically to stabilize nucleic acids even without cold chain8. Also, residue samples used for the rapid test kits, were used for PCR and subsequent sequencing analysis.