OBJECTIVES: This study aimed to extend an epidemiological model (SEIHFR) to analyze epidemic trends, and evaluate intervention efficacy. METHODS: SEIHFR was modified to examine disease transmission dynamics after vaccination for the Ebola outbreak. Using existing data from Liberia, sensitivity analysis of various epidemic scenarios was used to inform the model structure, estimate the basic reproduction number ℜ₀ and investigate how the vaccination could effectively change the course of the epidemic. RESULTS: If a randomized mass vaccination strategy was adopted, vaccines would be administered prophylactically or as early as possible (depending on the availability of vaccines). An effective vaccination rate threshold for Liberia was estimated as 48.74% among susceptible individuals. If a ring vaccination strategy was adopted to control the spread of the Ebola virus, vaccines would be given to reduce the transmission rate improving the tracing rate of the contact persons of an infected individual. CONCLUSION: The extended SEIHFR model predicted the total number of infected cases, number of deaths, number of recoveries, and duration of outbreaks among others with different levels of interventions such as vaccination rate. This model may be used to better understand the spread of Ebola and develop strategies that may achieve a disease-free state.
Africa, Western ; Basic Reproduction Number ; Disease Outbreaks ; Ebolavirus ; Humans ; Liberia ; Mass Vaccination ; Vaccination ; Vaccines

Zaire Ebola virus (EBOV) is a fatal human pathogen, with a high case fatality rate (CFR) averaging up to 78%. In March 2014, the World Health Organization (WHO) was made aware of a ZEBOV outbreak in rural Guinea, West Africa. Epidemiologic investigation linked the clinical and laboratory confirmed cases with the presumed first fatality of the outbreak in December 2013. EBOV from Guinea is a separate clade from other ZEBOV strains reported from the Democratic Republic of Congo (DRC) and Gabon. Since the outbreak in March, ZEBOV was also reported in Conakry, Guinea's capital and spread to other neighboring countries. In its largest outbreak, ZEBOV disease expanded through Guinea, Liberia, Sierra Leone, and Nigeria and to Spain, the USA, and the UK. The WHO declared the 2013-2015 West African Ebola epidemic a public health emergency of international concern considering its presumable capacity for further international spread. Early manifestations of EVD (Ebola virus disease) include a high fever, body aches, malaise, and fatigue. Severe diarrhea and other gastrointestinal manifestations such as vomiting were common, while bleeding was a more sporadic finding. The fatality rate was 43% and highest in patients aged > or = 45 years and the overall fitted mean incubation period was 10.3 days (95% CI 9.9~10.7). We present a review of the literature on the emergence of Ebola, and the epidemiologic, clinical, and laboratory records of patients in whom EVD was diagnosed in Sierra Leone, Guinea, Liberia, Mali, the USA, and Spain, its zoonotic origin, and the transmission of ZEBOV, as well as presenting original literature on the current Ebola outbreak.
Africa, Western* ; Congo ; Diarrhea ; Ebolavirus ; Emergencies ; Epidemiology ; Fatigue ; Fever ; Gabon ; Guinea ; Hemorrhage ; Humans ; Liberia ; Mali ; Mortality ; Nigeria ; Public Health ; Sierra Leone ; Spain ; Vomiting ; World Health Organization

OBJECTIVETo investigate and analyze AIDS knowledge of the Chinese peacekeepers in Liberia and to evaluate the effects of AIDS education in order to conduct more effective health education of AIDS and increase AIDS knowledge among the Chinese peacekeepers in the areas with a high incidence of AIDS.

METHODSA questionnaire was designed on the basis of that recommended by WHO to investigate the knowledge of AIDS among the 528 Chinese peacekeepers in Liberia respectively before and after relevant health education, and the results were compared.

RESULTSThere was an obvious deficiency in AIDS knowledge among the subjects before the education and an evident increase after it, and the difference was significant (P <0.01).

CONCLUSIONThe Chinese peacekeepers are deficient in AIDS knowledge, and the deficiency can be effectively improved by relevant health education, which is essential for the health of the Chinese peacekeepers in the areas with a high incidence of AIDS.

Acquired Immunodeficiency Syndrome ; Adult ; China ; Female ; Health Education ; Health Knowledge, Attitudes, Practice ; Humans ; Liberia ; Male ; Middle Aged ; Military Personnel ; Surveys and Questionnaires

OBJECTIVETo investigate the acceptability and influential factors of Voluntary HIV Counseling and Testing (VCT) among the Chinese and Ethiopian peacekeepers in Liberia so as to conduct more effective health education of AIDS and enhance the acceptance of VCT.

METHODSAn anonymous questionnaire was used to investigate the attitudes to VCT among 518 Chinese (aged 23-51) and 648 Ethiopian (aged 25-49) peacekeepers in Liberia.

RESULTSThe rates of those who claimed to have never heard of HIV/AIDS were 8.1% and 7.9% in the Chinese and Ethiopian subjects respectively, with no significant differences (P > 0.05) in between. Among those who had heard of HIV/ AIDS, 407 (85.5%) Chinese and 449 (75.2%) Ethiopians expressed their willingness to accept VCT, with a significant difference (P < 0.05) between the two groups. Statistic analysis indicated that the acceptance of VCT was as- sodiated with schooling and knowledge on HIV/AIDS in both groups as well as with the susceptibility to HIV among the Ethiopian subjects.

CONCLUSIONThe acceptability of VCT is obviously lower among those with less schooling and less knowledge of HIV/AIDS. It is important to carry out information-oriented education to increase VCT acceptability among the peacekeepers in the area with a high incidence of AIDS.

Acquired Immunodeficiency Syndrome ; prevention & control ; China ; Counseling ; methods ; statistics & numerical data ; Ethiopia ; Health Knowledge, Attitudes, Practice ; Humans ; Liberia ; Male ; Mass Screening ; methods ; psychology ; statistics & numerical data ; Military Personnel ; psychology ; Surveys and Questionnaires