Background: Mosquito-borne diseases such as dengue and chikungunya are endemic to tropical regions and are common causes of acute febrile illness in both adults and children. The Philippines, home to more than one hundred million residents and visited by several million tourists each year, is one such region where the risk of these diseases is endemic. Objective and Methods: To better understand the detailed situation, we estimated the proportion of these diseases in the community by conducting a prospective observational study in four provincial hospitals of Davao de Oro, Philippines, from February 2019 to February 2020. Sera from 382 study participants were used for laboratory confirmation of dengue or chikungunya by serology. Results: Dengue was diagnosed in 57.1%, chikungunya in 7.07%, and coinfection with both dengue and chikungunya in 7.3%, while the etiology was undetermined in 35.9% of the study participants. Common clinical symptoms included fever, headache, and a rash, which were overlapping symptoms that were clinically indistinguishable at the presentation to the hospital, necessitating laboratory diagnostics. Conclusions: The identification of the presence of chikungunya in Davao de Oro calls for increased awareness, improved diagnostics, and integrated disease control measures to manage outbreaks that can occur in dengue-endemic regions.

Paragonimus westermani is a food-borne zoonotic trematode transmitted to humans through the consumption of undercooked crustaceans. Freshwater crabs act as the second intermediate host for the encysted metacercariae stage. However, accurate identification of intermediate hosts remains a challenge. Here, we aimed to detect and identify P. westermani in randomly collected freshwater crabs and determine the species of infected crabs in Davao Oriental through molecular methods. Specifically, Sanger and next-generation sequencing were conducted for species identification through BLASTn, followed by phylogenetic analyses to understand geographic and taxonomic relationships. Results showed P. westermani DNA was detected in five out of eleven crab samples and these sequences were closely grouped to the Philippine reference sequence. Through a similar approach, the infected crabs showed high sequence similarity and formed tight clustering to Isolapotamon sp. Overall, the results provided evidence that P. westermani DNA was detected in Isolapotamon sp., a genus endemic to Mindanao, and can be a potential intermediate host. This expands our current understanding of transmission ecology beyond the only known intermediate host in the Philippines, Sundathelphusa philippina.

Background: Chikungunya virus (CHIKV) has circulated in the Philippines for more than six decades. We systematically reviewed the epidemiology of CHIKV in the Philippines, integrating evidence on transmission, seroprevalence, diagnostics and molecular lineages. Methods: We searched PubMed and Embase to March 2026 for original studies reporting incidence, prevalence, seroprevalence, outbreak characteristics, or surveillance findings in human populations in the Philippines. The gray literature from the Department of Health (DOH) Epidemiology Bureau’s national chikungunya surveillance (2018–March 2026) was included separately. Findings were synthesized narratively because of substantial heterogeneity. Results: Sixteen studies and one national surveillance dataset were included. National surveillance recorded 12,662 cases from 2018 to early 2026, including 722 laboratory-confirmed cases and three fatalities. The Asian genotype predominated during the 2011–2013 epidemic, while Indian Ocean lineage (IOL) viruses were detected in southern Mindanao. Conclusions: Transmission of CHIKV in the Philippines is mostly sporadic with periods of low-level transmission. Because the clinical features overlap with dengue, acute febrile illness surveillance should test for both viruses.

Background: Chikungunya virus (CHIKV) has circulated in the Philippines for more than six decades. Reviewing the evidence accumulated over this period provides an oppor-tunity to summarize its epidemiology and describe patterns of transmission over time. We systematically reviewed the epidemiology of CHIKV in the Philippines, integrating evidence on transmission, seroprevalence, diagnostics and molecular lineages. Methods: We followed PRISMA 2020 and searched PubMed and Embase to March 2026 for original studies reporting incidence, prevalence, seroprevalence, outbreak characteristics, or surveillance findings in human populations in the Philippines. Grey literature from the Department of Health (DOH) Epidemiology Bureau (2018–March 2026) was included separately. Findings were synthesized narratively because of substantial heterogeneity. Results: Sixteen studies and one national surveillance dataset were included. Serological reconstruction and prospective cohorts indicate approximately four major transmission waves over six decades, separated by intervals of about 17 years. Each wave infected an estimated 23% (16–37%) of remaining susceptible, while more than half remained sus-ceptible thereafter. In Cebu, incidence declined from 12.32 to 2.84 infections per 100 person-years as neutralizing-antibody prevalence increased from 28% to 42%; only about one in five infections was symptomatic. National surveillance recorded 12,662 cases from 2018 to early 2026, including 722 laboratory-confirmed; three deaths. The Asian genotype predominated during the 2011–2013 epidemic, while the Indian Ocean lineage viruses were detected in southern Mindanao. Conclusions: Transmission of CHIKV in the Phil-ippines appears to follow a periodic, recurrent pattern, with outbreaks occurring as population susceptibility accumulates following periods of low-level transmission. Pe-riodic arboviral serosurveys and testing of acute febrile illness are needed to better characterize CHIKV epidemiology in the Philippines.

Background: Dengue is endemic in the Maldives and remains a major public health concern in this small island nation of approximately half a million people. Genetic red blood cell disorders, particularly thalassemia, are common; however, the prevalence of other inherited disorders, such as glucose‐6‐phosphate dehydrogenase (G6PD) deficiency, remains poorly characterized. Despite this, sporadic cases of hemolytic anemia in G6PD deficient individuals have been reported. The presence of G6PD deficiency may alter the clinical course of acute dengue infection, as illustrated in the case presented, and require careful management to prevent complications. Case Presentation: A 22‐year‐old male presented with fever, headache, nausea, vomiting, and jaundice, which rapidly progressed to include epistaxis and dark‐colored urine. Laboratory findings revealed leukopenia, thrombocytopenia, elevated unconjugated bilirubin, markedly reduced G6PD activity, and elevated creatine kinase levels. While the dengue NS1 antigen test was positive during acute illness, follow‐up serology at 8 months remained negative. Conclusions: This case depicts the potential for concurrent hemolysis and rhabdomyolysis in G6PD‐deficient patients with dengue in endemic settings. Clinicians should maintain a high index of suspicion for these complications in patients presenting with fever and jaundice, as early recognition through vigilant clinical observation may influence management and clinical outcomes.