Case Report: Autoimmune Hemolysis Anemia After Dihydroartemisinin and Piperaquine for Uncomplicated Plasmodium falciparum Malaria

Malaria is still an endemic disease in Africa, with many imported cases in Europe. The standard treatment is intravenous artesunate for severe malaria and oral artemisinin-based combination therapy (ACT) for uncomplicated malaria. Delayed hemolytic anemia (DHA) after intravenous artesunate has been extensively described, and guidelines recommend biological monitoring until 1 month after the end of the treatment. A link with an autoimmune process is still unsure. Nevertheless, cases with positive direct antiglobulin test (DAT) have been reported. Conversely, DHA is not recognized as an adverse effect of oral ACT. Previously, only few cases of DHA occurring after oral ACT without intravenous artesunate administration have been reported. We report the case of a 42-year-old man returning from Togo. He was treated with dihydroartemisinin/piperaquine combination for uncomplicated Plasmodium falciparum malaria, with low parasitemia. Nine days after the end of the treatment, the patient developed hemolytic anemia with positive DAT. Eventually, the patient recovered after corticotherapy. After excluding common causes of autoimmune hemolytic anemia, we considered that dihydroartemisinin/piperaquine treatment was involved in this side effect.

Cost-Effectiveness of Public Health Measures to Control COVID-19 in China: A Microsimulation Modeling Study

This study aimed to assess the cost-effectiveness of various public health measures in dealing with coronavirus disease 2019 (COVID-19) in China. A stochastic agent-based model was used to simulate the progress of the COVID-19 outbreak in scenario I (imported one case) and scenario II (imported four cases) with a series of public health measures. The main outcomes included the avoided infections and incremental cost-effectiveness ratios (ICERs). Sensitivity analyses were performed to assess uncertainty. The results indicated that isolation-and-quarantine averted the COVID-19 outbreak at the lowest ICERs. The joint strategy of personal protection and isolation-and-quarantine averted one more case than only isolation-and-quarantine with additional costs. The effectiveness of isolation-and-quarantine decreased with lowering quarantine probability and increasing delay time. The strategy that included community containment would be cost-effective when the number of imported cases was >65, or the delay time of the quarantine was more than 5 days, or the quarantine probability was below 25%, based on current assumptions. In conclusion, isolation-and-quarantine was the most cost-effective intervention. However, personal protection combined with isolation-and-quarantine was the optimal strategy for averting more cases. The community containment could be more cost-effective as the efficiency of isolation-and-quarantine drops and the imported cases increases.

Cross-Border Malaria Drivers and Risk Factors on the Brazil-Venezuela Border Between 2016 and 2018

Background Globally, cross-border importation of malaria has become a challenge to malaria elimination. The border areas between Brazil and Venezuela have experienced high numbers of imported cases due to increased population movement and migration out of Venezuela. This study aimed to identify risk factors for imported malaria and delineate imported malaria hotspots in Roraima, Brazil and Bolivar, Venezuela between 2016 and 2018.MethodsData on malaria surveillance cases from Roraima, Brazil and Bolivar, Venezuela from 2016 to 2018 were obtained from national surveillance systems: the Brazilian Malaria Epidemiology Surveillance Information System (SIVEP-Malaria), the Venezuelan Ministry of Health and other non-government organizations. A multivariable logistic regression model was used to identify the risk factors for imported malaria. Spatial autocorrelation in malaria incidence was explored using Getis-Ord (Gi*) statistics.ResultsDuring the study period, there were 11,270 (24.3%) and 4,072 (0.7%) imported malaria cases in Roraima, Brazil and Bolivar, Venezuela, respectively. In the multivariable logistic regression for Roraima, men were 28% less likely to be an imported case compared to women (Adjusted Odds Ratio [AOR]= 0.72; 95% confidence interval [CI] 0.665, 0.781). Ages 20-29 and 30-39 were 90% (AOR=1.90; 95% CI 1.649, 2.181) and 54% (AOR=1.54; 95% CI 1.331, 1.782) more likely to be an imported case compared to the 0-9 year age group, respectively. Imported cases were 197 times (AOR=197.03; 95% CI 175.094, 221.712) more likely to occur in miners than those working in agriculture and domestic work. In Bolivar, cases aged 10-19 (AOR=1.75; 95% CI 1.389, 2.192), 20-29 (AOR=2.48; 95% CI 1.957, 3.144), and 30-39 (AOR=2.29; 95% CI 1.803, 2.913) were at higher risk of being an imported case than those in the 0-9 year old group, with older age groups having a slightly higher risk compared to Roraima. Compared to agriculture and domestic workers, tourism, timber and fishing workers (AOR=6.38; 95% CI 4.393, 9.254) and miners (AOR=7.03; 95% CI 4.903, 10.092) were between six and seven times more likely to be an imported case. Spatial analysis showed the risk was higher along the international border in the municipalities of Roraima, Brazil.ConclusionTo achieve malaria elimination, cross-border populations in the hotspot municipalities will need targeted intervention strategies tailored to occupation, age and mobility status. Furthermore, all stakeholders, including implementers, policymakers, and donors, should support and explore the introduction of novel approaches to address these hard-to-reach populations with the most cost-effective interventions.

Clinical features of 375 COVID-19 cases imported from Russia through the Suifenhe port and countermeasures

Background and objectives At present, the focus of the fighting against COVID-19 in China is shifting to strictly prevent the entrance of cases from abroad and disease transmission. Therefore, it is extremely urgent to better understand the clinical features of imported cases from overseas countries, which is conductive to formulate the corresponding countermeasures. This study aimed to describe the clinical features of COVID-19 cases imported from Russia through the Suifenhe port, in order to identify baseline and clinical data associated with disease progression and present corresponding countermeasures. Methods All COVID-19 cases imported from Russia through the Suifenhe port were included in this retrospective study. According to the “Diagnosis and Treatment Protocol for Novel Coronavirus Pneumonia (seventh edition)”, imported COVID-19 cases were divided into asymptomatic infection, mild, moderate, severe, and critical groups. Baseline and clinical data, including age, gender, comorbidities, disease severity, symptoms at onset, body temperature, white blood cell (WBC) count, lymphocyte (LYMPH) count, lymphocyte percentage (LYM%), C-reactive protein (CRP), oxygenation index (OI), and the use therapeutic modalities were obtained on admission, and then compared between groups. Results A total of 375 COVID-19 cases imported from Russia through Suifenhe port were included, of whom the asymptomatic infection, mild, moderate, severe, and critical groups accounted for 4.0%, 13.9%, 75.5%, 5.3%, and 1.3%, respectively. The majority of the imported COVID-19 cases were men (61.9%) with a median age of 38.72 years who had no comorbidity (87.7%). Nearly one-third of them (33.1%) were asymptomatic at onset, and common initial symptoms included fever (36.5%), cough (36.0%), pharyngeal discomfort (12.3%), expectoration (8.0%), and chest tightness (5.3%). In total, 180 (48%) and 4 (1.1%) enrolled imported cases received nasal tube oxygen inhalation therapy and high-flow oxygen absorption, respectively; the remaining patients did not undergo oxygen therapy. The values of age, body temperature, WBC, LYMPH, LYM%, CRP, and OI were 38.72 ± 10.50, 35.10 ± 7.92, 5.59 ± 1.97, 1.67 ± 0.68, 31.05 ± 10.22, 8.00 ± 14.75, and 389.03 ± 74.07, respectively. Gender, age, LYMPH, LYM%, symptoms at onset, cough, fever, other rare symptoms, and oxygen therapy showed significant differences between groups (P = 0.036, < 0.001, < 0.001, < 0.001, < 0.001, < 0.001, < 0.001, = 0.045, < 0.001, respectively). Conclusions Compared with domestic confirmed patients, COVID-19 patients who arrived at China from Russia through the Suifenhe port had significantly different clinical features, and the differences in gender, age, LYMPH, LYM%, symptoms at onset, cough, fever, other rare symptoms, and oxygen therapy between groups were statistically significant. Therefore, detailed and comprehensive countermeasures were developed to manage and prevent another outbreak based on these clinical features.

Contact network analysis of Covid-19 in tourist areas——Based on 333 confirmed cases in China

The spread of infectious diseases is highly related to the structure of human networks. Analyzing the contact network of patients can help clarify the path of virus transmission. Based on confirmed cases of COVID-19 in two major tourist provinces in southern China (Hainan and Yunnan), this study analyzed the epidemiological characteristics and dynamic contact network structure of patients in these two places. Results show that: (1) There are more female patients than males in these two districts and most are imported cases, with an average age of 45 years. Medical measures were given in less than 3 days after symptoms appeared. (2) The whole contact network of the two areas is disconnected. There are a small number of transmission chains in the network. The average values of degree centrality, betweenness centrality, and PageRank index are small. Few patients have a relatively high contact number. There is no superspreader in the network.

CRIMEAN HAEMORRHAGIC FEVER IN A CHILD AFTER A VISIT TO CRIMEA

This article contains additional information on the features of the clinical picture of Crimean hemorrhagic fever (CHF) in children, the ongoing activity of CHF virus circulation in the territory of the Republic of Crimea, confirms the possibility of imported cases of CHF in non-endemic regions, which is associated with the likely risks of nosocomial and intrafamilial cases of this infection. The data on the course of the disease, clinical and laboratory diagnostic examination of a child infected with CHF in the Crimea are presented.

Estimating the number of undetected COVID-19 cases among travellers from mainland China

Background: As of August 2021, every region of the world has been affected by the COVID-19 pandemic, with more than 196,000,000 cases worldwide. Methods: We analysed COVID-19 cases among travellers from mainland China to different regions and countries, comparing the region- and country-specific rates of detected and confirmed cases per flight volume to estimate the relative sensitivity of surveillance in different regions and countries. Results: Although travel restrictions from Wuhan City and other cities across China may have reduced the absolute number of travellers to and from China, we estimated that up to 70% (95% CI: 54% - 80%) of imported cases could remain undetected relative to the sensitivity of surveillance in Singapore. The percentage of undetected imported cases rises to 75% (95% CI 66% - 82%) when comparing to the surveillance sensitivity in multiple countries. Conclusions: Our analysis shows that a large number of COVID-19 cases remain undetected across the world. These undetected cases potentially resulted in multiple chains of human-to-human transmission outside mainland China.

A nucleic acid-based orthopoxvirus vaccine targeting the vaccinia virus L1, A27, B5 and A33 proteins protects rabbits against lethal rabbitpox virus aerosol challenge

In the age of COVID, nucleic acid vaccines have garnered much attention, at least in part, because of the simplicity of construction, production, and flexibility to adjust and adapt to an evolving outbreak. Orthopoxviruses remain a threat on multiple fronts, especially as emerging zoonosis. In response, we developed a DNA vaccine, termed 4pox, that protected nonhuman primates against monkeypox virus (MPXV) induced severe disease. Here, we examined the protective efficacy of the 4pox DNA vaccine delivered by intramuscular (i.m.) electroporation (EP) in rabbits challenged with aerosolized rabbitpox virus (RPXV), a model that recapitulates the respiratory route of exposure and low dose associated with natural smallpox exposure in humans. We found that 4pox vaccinated rabbits developed immunogen-specific antibodies, including neutralizing antibodies and did not develop any clinical disease, indicating protection against aerosolized RPXV. In contrast, unvaccinated animals developed significant signs of disease, including lesions, and were euthanized. These findings demonstrate that an unformulated, non-adjuvanted DNA vaccine delivered (i.m.) can protect against an aerosol exposure. Importance The eradication of smallpox and subsequent cessation of vaccination has left a majority of the population susceptible to variola virus or other emerging poxvirus. This is exemplified by human monkeypox, as evidenced by the increase in reported endemic and imported cases over the past decades. Therefore, a malleable vaccine technology that can be mass produced, and doesn’t require complex conditions for distribution and storage is sought. Herein, we show that a DNA vaccine, in the absence of a specialized formulation or adjuvant, can protect against a lethal aerosol insult of rabbitpox virus.