Epidemiological characteristics of Lassa fever cases in Liberia: a retrospective analysis of surveillance data, 2019-2020.

OBJECTIVES: Liberia is endemic to Lassa fever (LF) and has the largest reported per capita incidence of LF patients in the West African region. Cases of the disease increased unprecedentedly in 2019 and 2020, characterized by a geographical drift in epidemiology and seasonal variation of occurrence. This study aims to describe the epidemiological and clinical characteristics of LF in Liberia from 2019 to 2020. METHODS: A retrospective study was conducted on cases of LF confirmed at the National Public Health Reference Laboratory from January 2019 to December 2020. Medical records were reviewed, and epidemiological and clinical data were collected in an organized manner. Descriptive and inferential statistics were carried out using Epi Info (version 7.2.5.0). RESULTS: A total of 382 suspected LF cases were reported, of which 103 were laboratory-confirmed, yielding a case positivity rate of 27% (103/382). The median age of the LF cases was 20 (IQR: 9-30). Children younger than 18 years accounted for 40.8% (42/103) of the cases and healthcare workers' cases constituted 7.7% of the cases. Bong, Nimba, and Grand Bass accounted for 87.4% of the cases with cases in new counties like Lofa, Margibi, and Grand Kru. Hemorrhage (aOR:10.2; 95% CI: 3.11-33.81), patients who did not receive ribavirin (aOR: 4.4; 95% CI: 1.12-17.57, P = 0.034), and patients aged 40 years or older (aOR: 6.2; 95% CI: 1.19-32.53, P = 0.049) were associated with LF mortality. CONCLUSION: The LF cases in 2019 and 2020 had a high case fatality rate and spread to new counties that had not previously reported LF. The disease occurred during most of the rainy season instead of the usual dry season. There is an urgent need to lower morbidity and mortality, improve early presentation to the hospital, and early initiation of appropriate medical care.

Rapid Laboratory Identification of Neisseria meningitidis Serogroup C as the Cause of an Outbreak - Liberia, 2017.

On April 25, 2017, a cluster of unexplained illness and deaths among persons who had attended a funeral during April 21-22 was reported in Sinoe County, Liberia (1). Using a broad initial case definition, 31 cases were identified, including 13 (42%) deaths. Twenty-seven cases were from Sinoe County (1), and two cases each were from Grand Bassa and Monsterrado counties, respectively. On May 5, 2017, initial multipathogen testing of specimens from four fatal cases using the Taqman Array Card (TAC) assay identified Neisseria meningitidis in all specimens. Subsequent testing using direct real-time polymerase chain reaction (PCR) confirmed N. meningitidis in 14 (58%) of 24 patients with available specimens and identified N. meningitidis serogroup C (NmC) in 13 (54%) patients. N. meningitidis was detected in specimens from 11 of the 13 patients who died; no specimens were available from the other two fatal cases. On May 16, 2017, the National Public Health Institute of Liberia and the Ministry of Health of Liberia issued a press release confirming serogroup C meningococcal disease as the cause of this outbreak in Liberia.

Lateral Flow Immunoassays for Ebola Virus Disease Detection in Liberia.

BACKGROUND: Lateral flow immunoassays (LFIs) are point-of-care diagnostic assays that are designed for single use outside a formal laboratory, with in-home pregnancy tests the best-known example of these tests. Although the LFI has some limitations over more-complex immunoassay procedures, such as reduced sensitivity and the potential for false-positive results when using complex sample matrices, the assay has the benefits of a rapid time to result and ease of use. These benefits make it an attractive option for obtaining rapid results in an austere environment. In an outbreak of any magnitude, a field-based rapid diagnostic assay would allow proper patient transport and for safe burials to be conducted without the delay caused by transport of samples between remote villages and testing facilities. Use of such point-of-care instruments in the ongoing Ebola virus disease (EVD) outbreak in West Africa would have distinct advantages in control and prevention of local outbreaks, but proper understanding of the technology and interpretation of results are important. METHODS: In this study, a LFI, originally developed by the Naval Medical Research Center for Ebola virus environmental testing, was evaluated for its ability to detect the virus in clinical samples in Liberia. Clinical blood and plasma samples and post mortem oral swabs submitted to the Liberian Institute for Biomedical Research, the National Public Health Reference Laboratory for EVD testing, were tested and compared to results of real-time reverse transcription-polymerase chain reaction (rRT-PCR), using assays targeting Ebola virus glycoprotein and nucleoprotein. RESULTS: The LFI findings correlated well with those of the real-time RT-PCR assays used as benchmarks. CONCLUSIONS: Rapid antigen-detection tests such as LFIs are attractive alternatives to traditional immunoassays but have reduced sensitivity and specificity, resulting in increases in false-positive and false-negative results. An understanding of the strengths, weaknesses, and limitations of a particular assay lets the diagnostician choose the correct situation to use the correct assay and properly interpret the results.

Single­incision technique for the internal fixation of distal fractures of the tibia and fibula: a combined anatomic and clinical study.

OBJECTIVES: To present a novel single anterior-lateral approach for the treatment of distal tibia and fibula fracture via anatomical study and primary clinical application in order to minimize soft tissue complications. DESIGN: Both a gross anatomic cadaver and retrospective studies of the single-incision technique in patients recruited between June 2004 and January 2010. SETTING: Level I trauma center. PATIENTS/PARTICIPANTS: Twenty-six legs of 14 adult human cadavers and clinical recruitment of 49 patients (29 males, 20 females) with a mean age of 37.6 years (range 11-68) with fracture of distal 1/3 tibia and fibula. INTERVENTION: A single anterior-lateral incision technique for open reduction and internal fixations of distal tibia and fibula fractures. MAIN OUTCOME MEASURES: To identify the anatomic structures at risk in the anterolateral aspect of the lower leg and explicit the safe dissection distance from the extensor digitorum longus (EDL) to tibia and fibula, 26 legs of 14 adult human embalmed specimens were recruited in the anatomical study with the distance between the EDL and the anterior edge of the distal thirds of the tibia, as well as the distance between the EDL and the anterior edge of the distal thirds of the fibula were measured, and their mutual relationships to the surrounding anatomical structures described. Mean average standard deviations were also calculated. As for the clinical study, the quality of bone union and soft tissue healing were noted. RESULTS: The mean distances between the distal tibia and the EDL were measured to be 2.96 ± 0.46 cm (proximal), 1.85 ± 0.25 cm (middle), and 2.15 ± 0.30 cm (distal), and that between the fibula and the EDL were 1.82 ± 0.28 cm (proximal), 2.09 ± 0.31 cm (middle), and 2.30 ± 0.27 cm (distal), which means the safe gap from the distal tibia to EDL was 1.6-3.4 cm and from the EDL to fibula was 1.5-2.6 cm. The anterior tibial vein and artery and the deep fibular nerve lie on the anterior interosseous membrane over the lateral surface of the distal tibia were excellently visualized. Review of clinical outcomes in 49 patients with combined distal tibial and fibular fractures who underwent reduction and fixation with the single-incision technique, revealed uneventful fracture healings in 47 patients; and two cases of superficial wound necrosis which were treated and healed in 4 months. There was no case of delayed union or non-union. CONCLUSION: Distal fibula fracture occurring with distal tibia fracture poses a challenge for stable fixation. This has necessitated the need for dual incisions on the distal leg to approach each fracture for reduction and fixation. However, a single anterolateral incision enables the safe approach to the lateral aspects of the distal tibia and fibula thus eliminating the need for two separate incisions and minimizing the soft tissue complication to some extent. Meanwhile, the neurovascular bundle at risk during operation, distal tibia and fibula is clearly exposed in the single anterior-lateral incision.