Asymptomatic malaria infection at the China-Vietnam border: Knowledge and implications for the cross-border migrant population during the COVID-19 pandemic

Prevalence and proportion estimate of asymptomatic Plasmodium infection in Asia: a systematic review and meta-analysis

Asymptomatic Plasmodium infection raises a problem for the persistent transmission of malaria in low-endemic areas such as Asia. This systematic review was undertaken to estimate the prevalence and proportion of asymptomatic Plasmodium infection in Asia. The systematic review was registered at PROSPERO (ID: CRD42022373664). The research followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. A comprehensive search of five databases, Ovid, Scopus, MEDLINE, PubMed, and Embase, was conducted to identify studies of asymptomatic Plasmodium infection in Asian countries. The pooled prevalence of asymptomatic Plasmodium infection, the pooled proportion of asymptomatic Plasmodium infection among all parasitised individuals, and the associated 95% confidence intervals were estimated using a random-effects model. A total of 916 articles were retrieved, and 87 articles that met the criteria were included in the systematic review. The pooled prevalence of asymptomatic Plasmodium infection among enrolled participants in Southeast Asia, South Asia, and Western Asia was 5.8%, 9.4%, and 8.4%, respectively. The pooled proportion of asymptomatic Plasmodium infection among all parasitised individuals in Southeast Asia, South Asia, and Western Asia was 89.3%, 87.2%, and 64.8%, respectively. There was a low prevalence of asymptomatic Plasmodium infection, but there was a high proportion of asymptomatic Plasmodium infection per all parasitised individuals in different parts of Asia. These results may support and facilitate elimination and control programs for asymptomatic Plasmodium infection in Asia.

Imported malaria from land bordering countries in China: A challenge in preventing the reestablishment of malaria transmission

OBJECTIVE

No indigenous malaria cases have been reported since 2017 in China, but a large number of imported cases are still reported every year, including those from the land bordering countries. To characterize their epidemiological profiles will provide evidence for the development of appropriate strategies to effectively address the challenges of border malaria in the post-elimination phase.

METHODS

Individual-level data of imported malaria cases from the land bordering countries were collected from 2017 to 2021 in China via the web-based surveillance systems, and analyzed by SPSS, ArcGIS and WPS software, to explore their epidemiological profiles.

RESULTS

A total of 1170 malaria cases imported into China from six of the fourteen land bordering countries were reported between 2017 and 2021 with a decline trend. Overall, cases were widely distributed in 31-97 counties from 11 to 21 provinces but mainly in Yunnan. Moreover, these imported cases were mainly infected with P. vivax (94.8%), and a total of 68 recurrent cases were reported in 6-14 counties from 4 to 8 provinces. In addition, nearly 57.1% of the total reported cases could seek healthcare within 2 days of getting sick, and 71.3% of the reported cases could be confirmed as malaria on the day they sought medical care.

CONCLUSIONS

China still needs to attach great importance to the risk and challenge of the imported malaria from bordering countries particularly from Myanmar in preventing reestablishment of malaria transmission in the post-elimination phase. It is necessary not only to strengthen collaboration and cooperation with the bordering countries, but also coordinate multiple departments at home to improve malaria surveillance and response system and prevent the reestablishment of malaria transmission in China.

Self-employment and health inequality of migrant workers

Background

Self-employment is one of the most common forms of employment for migrant workers in China. However, migrant workers’ lifestyle and behavior, as well as health disparities among them, would be impacted by self-employment. This research aims to explore the mechanism and group differences of the effect of self-employment on health inequality among Chinese migrant workers.

Materials and methods

To explore the effect of self-employment on health inequalities among migrant workers, this research uses the data from the 2018 China Migrant Workers Dynamic Monitoring Survey, and the RIF-I-OLS decomposition method.

Results

We find that self-employment will reduce the health inequality of Chinese migrant workers significantly, especially among migrant workers with low education, low income, and low social integration. A further examination reveals that self-employment can directly promote the self-rated health of migrant workers. Additionally, it indirectly alleviates the health inequality among migrant workers by mediating effect of expanding access to public welfare, such as by establishing health records and strengthening health education.

Conclusion

The government should permit and encourage migrant workers to engage in self-employment. It is necessary to provide public services such as health education, health records, and health rights for migrant workers, and focus on the employment of migrant workers in city, especially those with low income and low education. we believe that measures should be taken to enhance migrant workers’ sense of belonging in urban China Only on this basis can health inequality among migrant workers be truly reduced.