Historical drivers of HCV Subtypes 1b and 3a in Thailand and 6f in Phetchabun, an HCV endemic area of the country.

The World Health Organization has set a target to eliminate viral hepatitis as a public threat by 2030. In pursuit of this goal, Thailand initiated a hepatitis C virus (HCV) microelimination project targeting Phetchabun province, a well-recognized high-burden HCV endemic area. However, the historical transmission dynamics of HCV in Phetchabun, and in Thailand in general, remain unclear. This study investigates the epidemic histories of HCV in Phetchabun, focusing on Subtypes 1b, 3a, and 6f, and their relationship with HCV in other regions of Thailand, using molecular phylogenetic analyses. Our results reveal nationwide the presence of Subtypes 1b and 3a, while Subtype 6f is mainly confined to Phetchabun. The initial spread of Subtype 1b was inferred to coincide with World War II and the period of suboptimal medical and hygienic standards in Thai blood transfusion services, suggesting a correlation between the two. The early expansion of Subtype 3a was, on the other hand, found to correlate with the epidemic of intravenous drug use in Thailand during the time of Vietnam War. The early expansion of Subtype 6f, in contrast, appears to coincide with the period of severe regional political conflict and social and economic instability. All these findings suggest the complex interplay between social determinants of health and HCV transmission. Post the mid-1990s/early 2000s, all subtypes showed significantly reduced population growth rates, aligning with improvements in blood transfusion safety standards, the nationwide "War on Drugs" policy, and enhanced accessibility to public healthcare and HCV treatments. These combined efforts likely have contributed to curbing the spread of HCV in Thailand. Nevertheless, our analyses reveal that the prevalence of HCV in Thailand remains high overall, emphasizing the need for further research and a nationwide approach to more effectively reduce the HCV burden in Thailand.

Overview of the epidemic history of Hepatitis C uncommon subtypes 2i and 4d in Tunisia and in the world.

The impressive improvements in qua therapy efficacy alone are not sufficient to substantially reduce the Hepatitis C Virus burden because of the usually very long asymptomatic phase of the infection. In turn, this renders prevention of infection of great importance. The value of learning how the virus has spread in the past is that this can provide clues as to what routes the virus likely spreads through today, which can feedback into prevention policy. In Tunisia, HCV subtypes 2i and 4d are minor circulating subtypes. Here, we applied a Bayesian Markov Chain Monte Carlo method for visualization of spatial and temporal spread of HCV-2i and 4d in Tunisia and some other countries in the world. Our analysis included sequences retrieved from Genbank and isolated from several countries in the world; 21 HCV-NS5B subtype 2i genome sequences obtained during the period 2002-2020 and 206 HCV-NS5B-4d sequences detected between 2000 and 2019. Phylogenetic analysis revealed that two geographical clusters could be identified in HCV-2i tree with two clearly distinguished clusters in HCV-4d Tree. The estimated time for the most recent common ancestor suggested that current HCV-2i strains emerged in 1963 [1930, 1995] and current HCV-4d strains emerged in 1992 [1988, 1996] in Tunisia and other countries from the world investigated in the present study.

Geographic Transmission and Epidemic History of HIV-1 CRF01_AE, CRF07_BC, and HCV Subtype-6w among Taiwanese Persons Who Inject Drugs.

Persons who inject drugs (PWID) and their risk-related behaviors (e.g., unprotected sex and sharing needles/syringes/other injection equipment) have caused severe public health problems, especially in the rapid spread of HIV-1 and HCV. Here, we reconstructed the epidemic history of HIV-1 circulating recombinant form (CRF) 01_AE, CRF07_BC, and HCV subtype-6w among Taiwanese PWID. The timescales were estimated using phylogenetic and Bayesian coalescent analyses. The results revealed that CRF01_AE started to circulate in the Taiwanese PWID population in central Taiwan at 1992.5 (95% credible region: 1988.8-1995.9) and spread to other regions of Taiwan, while CRF07_BC was first identified in southern Taiwan at 2000.0 (95% CR: 1997.8-2002.2) and then spread northward to central-northern Taiwan. All HCV-6 strains were from Asia (that is, China, Myanmar, Taiwan, and Vietnam) and originated in 1928.1 (95% CR: 1890.2-1966.0). Furthermore, subtype-6w isolates from different regions of Taiwan appeared to share a common source that existed in the mid-1990s (95% CR: 1985.0-2001.8) or thereabouts. The routes of drug trafficking and the resulting high prevalence of HIV-1/HCV co-infections among PWID might have contributed to the virus transmission and promoted its spread worldwide. Long-term monitoring and policy implementation in at-risk populations would be useful for disease control.

The prevalence of CRF55_01B among HIV-1 strain and its connection with traffic development in China.

CRF55_01B is a relatively "young" HIV strain. At present, we do not know much about its transmission characteristics in China. So, to describe the transmission characteristics of CRF55_01B strain among provinces and HIV infected people, and to analyze the reasons for its rapid epidemic in China, a total of 1237 subjects infected with CRF55_01B from 31 provinces spanning a period of 12 years from 2007 to 2018 were enrolled in this study. By constructing a molecular network and Bayesian correlation analysis, we found that CRF55_01B increased exponentially from 2005 to 2009 after its origin in Shenzhen, and increased rapidly after 2010. CRF55_01B began to spread to other provinces in 2007. After 2010, the strain showed a trend of rapid spread and epidemic from Guangdong-Shenzhen to other provinces in China. Guangdong, Shenzhen, Hunan, Beijing, Guangxi, Hubei, Jiangxi, Guizhou, Hebei, Anhui, Shanghai, Shandong, Henan, and Yunnan were the key provinces of CRF55_01B transmission. CRF55_01B, although originating from men who sex with men (MSM), was transmitted among heterosexuals in 2010. Males in heterosexuals played a crucial role in the transmission and diffusion of this strain. We also revealed that CRF55_01B might spread rapidly along with the rapid development of the Beijing-Guangzhou and Beijing-Kowloon railways. This study suggests that if we detect the spread of MSMs in time through molecular monitoring in the early stage of the epidemic, it can help us control the epidemic early and prevent its spread, which is of great significance to China's national prevention and control of HIV-1.

Characteristics of respiratory virus infection during the outbreak of 2019 novel coronavirus in Beijing.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is spreading. Here, we summarized the composition of pathogens in fever clinic patients and analyzed the characteristics of different respiratory viral infections. METHODS: Retrospectively collected patients with definite etiological results using nasal and pharyngeal swabs in a fever clinic. RESULTS: Overall, 1860 patients were screened, and 136 patients were enrolled. 72 (52.94%) of them were diagnosed as influenza (Flu) A virus infection. 32 (23.53%) of them were diagnosed as Flu B virus infection. 18 (13.24%) and 14 (10.29%) of them were diagnosed as COVID-19 and respiratory syncytial virus (RSV) infections, respectively. The COVID-19 group had a higher rate of contact with the epidemic area within 14 days and of clustering onset than other groups. Fever was the most common symptom in these patients. The ratio of fever to the highest temperature was higher in Flu A virus infection patients than in COVID-19 patients. COVID-19 patients had a lower white blood cell count and neutrophil count than Flu A virus and RSV infection groups, but higher lymphocyte count than Flu A and B virus infection groups. The COVID-19 group (83.33%) had a higher rate of pneumonia in chest CT scans than Flu A and B virus infection groups. CONCLUSIONS: Influenza viruses accounted for a large proportion of respiratory virus infection even during the epidemic of COVID-19 in Beijing. No single symptom or laboratory finding was suggestive of a specific respiratory virus; however, epidemic history was significant for the screening of COVID-19.

Recurrent Cholera Outbreaks, Democratic Republic of the Congo, 2008-2017.

In 2017, the exacerbation of an ongoing countrywide cholera outbreak in the Democratic Republic of the Congo resulted in >53,000 reported cases and 1,145 deaths. To guide control measures, we analyzed the characteristics of cholera epidemiology in DRC on the basis of surveillance and cholera treatment center data for 2008-2017. The 2017 nationwide outbreak resulted from 3 distinct mechanisms: considerable increases in the number of cases in cholera-endemic areas, so-called hot spots, around the Great Lakes in eastern DRC; recurrent outbreaks progressing downstream along the Congo River; and spread along Congo River branches to areas that had been cholera-free for more than a decade. Case-fatality rates were higher in nonendemic areas and in the early phases of the outbreaks, possibly reflecting low levels of immunity and less appropriate prevention and treatment. Targeted use of oral cholera vaccine, soon after initial cases are diagnosed, could contribute to lower case-fatality rates.

Phylogenetic and phylodynamic analyses of hepatitis C virus subtype 1a in Okinawa, Japan.

Okinawa Island, located in Southern Japan, has a higher prevalence rate of hepatitis C virus subtype 1a (HCV-1a) infection than that in mainland Japan. Okinawa has a history of US military occupation after World War II. To elucidate the transmission history of HCV-1a in Okinawa, 26 whole-genome sequences were obtained from 29 patients during 2011-2016. Phylogenetic trees were reconstructed to identify the origin and characteristics of HCV-1a in Okinawa with epidemiological information. A phylogenetic tree based on whole-genome sequencing revealed that all of the samples were located below the US branches. Additionally, we identified one cluster comprised of 17 strains (Okinawa, n = 16; United States, n = 1). The majority of the patients in this cluster were people who inject drugs (PWID), indicating the presence of a people who inject drugs (PWID) cluster. Subsequently, Bayesian analyses were employed to reveal viral population dynamics. Intriguingly, a phylodynamic analysis uncovered a substantial increase in effective population size of HCV-1a from 1965 to 1980 and a slight increase in mid-2000, which were associated with an increase in illicit drug use in Okinawa. The estimated divergence time of the PWID cluster was 1967.6 (1964.2-1971.1). These findings suggest that HCV-1a was introduced into Okinawa from the United States in the late 1960s, coincident with the Vietnam War. Subsequently, HCV-1a might have spread among the Japanese population with the spread of injecting drug use. Our study provides an understanding of HCV transmission dynamics in Okinawa, as well as the key role of PWID in HCV transmission.