Neglected Time Intervals Before “1-3-7” Approach About Imported Malaria Cases — China, 2014–2021

   A recent study analyzed 4,614 imported malaria cases in China from 2014–2021, revealing differences in symptom onset and treatment timelines across Plasmodium species. P. falciparum had the shortest intervals from arrival to symptom onset (median 6 days) and symptom onset to treatment (median 2 days). P. ovale and P. vivax showed extended arrival-to-symptom intervals (78 and 42 days, respectively) but brief symptom-to-treatment durations. Conversely, P. malariae had a shorter arrival-to-symptom timeline (24.5 days) but longer symptom-to-treatment period (4 days). The findings highlight the need for malaria education for overseas arrivals, particularly from Africa and Southeast Asia, and increased diagnostic vigilance to prevent severe cases and fatalities as China maintains its malaria-free status.

   For more information: https://weekly.chinacdc.cn/en/article/doi/10.46234/ccdcw2024.070

Genome Analysis of Plasmodium falciparum: A Preliminary Observation — Sierra Leone, 2022

   Scientists have sequenced the genomes of malaria parasites from Sierra Leone for the first time, revealing unique characteristics of the parasite population in this high-burden country. The study found elevated genetic diversity, particularly in gene families linked to the parasite’s ability to invade red blood cells and evade the immune system. Drug resistance genes showed signs of strong selection pressure, potentially due to local treatment practices. These findings highlight the need for ongoing genomic surveillance to inform malaria control strategies tailored to the distinct genetic makeup of the parasite population in Sierra Leone. Understanding these variations is crucial for developing effective interventions and monitoring the ever-evolving landscape of malaria in high-risk regions.

   For more information: https://weekly.chinacdc.cn/en/article/doi/10.46234/ccdcw2024.071

Situational Analysis of Malaria Incidence Under Integrated Malaria Service in Hotspot Township — Minbya Township, Rakhine State, Myanmar, 2017–2020

   A study in Myanmar's Minbya Township reveals significant progress in reducing malaria cases through integrated community health services and intensified control strategies. Despite challenges posed by COVID-19, the National Malaria Control Program, in collaboration with local volunteers, has effectively maintained malaria testing and treatment capacity. The annual parasite index decreased from 3 in 2015 to 2.5 in 2020, with a decline in malaria cases from 2,804 to 514 during the same period. The study highlights the importance of active case detection, rapid diagnostic testing, and the distribution of long-lasting impregnated bed nets in high-risk areas. The findings suggest that early detection and treatment strategies in malaria hotspots should be part of a comprehensive approach to reducing the disease burden in Myanmar.

   For more information: https://weekly.chinacdc.cn/en/article/doi/10.46234/ccdcw2024.072

Cooperative Sentinel Surveillance of Malaria in Laiza and Nearby Areas of Myanmar and Importation Threat Monitoring — China, 2019–2023

   A recent study has revealed a significant resurgence of malaria in the Laiza and nearby areas (LNA) of Myanmar, with the annual parasite incidence increasing by 21.47 times and the positivity rate of laboratory tests surging by 10.58 times in 2023 compared to 2019. This resurgence has led to a high number of malaria cases being imported into China, with 53.64% of the total malaria cases in Yunnan Province originating from LNA between 2019 and 2023. The imported cases have spread to 18 counties in Yunnan and nine other provinces in China. The study highlights the need for innovative collaborative policies, financial support, and technical assistance to control malaria along the border and prevent further transmission into China.

   For more information: https://weekly.chinacdc.cn/en/article/doi/10.46234/ccdcw2024.073