Modelling of Hepatitis B Virus vertical transmission dynamics in Ethiopia: a compartmental modelling approach

BACKGROUND

Hepatitis B (HB) is a virus which causes a potentially fatal liver infection. It is a DNA virus belonging to the Hepadnaviridae virus family. Africa, after Asia, has the second highest number of chronic HBV carriers and is considered a high-endemic region. Ethiopia is classified as a country with a high prevalence of viral hepatitis and with nations that lack a systematic strategy for viral hepatitis surveillance.

METHODS

S-I-C-R deterministic model was developed and the numerical simulations were done in "R" statistical and programming software. Fixed population assumption was considered so as to develop a simple model which could predict the HBV vertical transmission for the next 5 decades.

RESULTS

The model revealed that significant number of populations will be infected and become carrier till the end the next 49 years even though it has decreasing trend. It was predicted that 271,719 people will die of HBV complications if no intervention will be made on its vertical transmission. The sensitivity analysis result showed that the force of infection has the most important parameter in the vertical transmission dynamics of hepatitis B. Provision of hepatitis B immunoglobulin (HBVIG) and vaccines at the time of delivery could decrease the force of infection by more than half and 51,892 lives will be saved if the intervention is offered for 50% of deliveries in Ethiopia.

CONCLUSION

Despite the fact that the incidence of HBV vertical transmission is substantial, it is expected to decline during the next five decades. However, the situation necessitates immediate attention, since it results in thousands of deaths if no action is taken. Offering HBVIG and vaccinations to the 50% of infants can save many lives and reduces the force of infection by more than a half.

Evaluation of thromboembolic event, basic coagulation parameters, and associated factors in patients with colorectal cancer: a multicenter study

Background

Patients with colorectal cancer are at an increased risk of hemostatic disturbances, and recent studies have shown that coagulation disorders could be the first sign of malignancy. Although coagulopathy is a significant cause of cancer-related death and disability, it is usually underestimated, and there has been no recent scientific evidence regarding the exact burden and its specific determinants. Moreover, the public health importance of the risk of coagulopathy among patients with colorectal polyps has not been addressed.

Materials and methods

An institution-based comparative cross-sectional study was conducted on a total of 500 study participants (250 colorectal cancer patients, 150 colorectal polyp patients, and 100 controls) from January to December 2022. Venous blood was collected for basic coagulation and platelet analysis. Descriptive statistics and non-parametric tests (Kruskal-Wallis and Dunn-Bonferroni pairwise comparisons) were used to compare study parameters among the groups. The test results were expressed as medians and interquartile ranges. Binary logistic regressions were fitted, and statistical significance was declared at a p-value of less than 0.05, with 95% CI.

Results

The prevalence of coagulopathy among colorectal cancer patients was 198 (79.2%; 95% CI: 73.86, 83.64), while the prevalence was 76 (50.7%; 95% CI: 45.66, 54.34) among colorectal polyp patients. From the final model, age between 61 and 70 (AOR = 3.13: 95% CI: 1.03, 6.94), age > 70 years (AOR = 2.73: 95% CI: 1.08, 4.71), hypertension (AOR = 6.8: 95% CI: 1.07, 14.1), larger tumor size (AOR = 3.31: 95% CI: 1.11, 6.74), metastatic cancer (AOR = 5.8: 95% CI: 1.1, 14.7), and BMI ≥30 kg/m² (AOR = 3.8: 95% CI: 2.3, 4.8) were positively associated with coagulopathy.

Conclusion

This study showed that coagulopathy is a major public health concern among patients with colorectal cancer. Therefore, existing oncology care efforts should be strengthened to prevent coagulopathy among patients with colorectal cancer. Moreover, patients with colorectal polyps should receive more attention.

Evaluation of total oxidative stress and antioxidant capacity of brain tumour patients attending referral hospitals in Addis Ababa, 2020: a comparative cross-sectional study

Background

The exact cause of brain tumours is still unknown, but disruptions of redox balance are thought to play a significant role in all stages of brain tumour development. However, the roles of free radical imbalance at different grades of brain tumour and degree of oxidative stress before and after surgery have not been addressed in prior studies.

Aim

A comparative cross-sectional study was conducted to assess the redox imbalance among confirmed brain tumour patients.

Methods and results

An institution-based comparative cross-sectional study was conducted on a total of 100 participants (50 brain tumour patients and 50 controls) at referral hospitals in Addis Ababa, Ethiopia. Descriptive statistics, t-test and analysis of variance (ANOVA) (post-hoc) analysis were used and statistical significance was declared at p ≤ 0.05. The serum oxidised glutathione and total oxidative stress were significantly higher in the serum of brain tumour patients (0.72 ± 0.03 μM/μg and 9.66 ± 1.76 μmol H2O2 Eq/L, respectively) compared to the control group (0.21 ± 0.07 μM/μg and 6.59 ± 0.81 μmol H2O2 Eq/L, respectively) (p ≤ 0.05). The serum total oxidant status gradually increased as the tumour grade increased, being higher in grade four (11.96 ± 0.72) and lower in grade one (8.43 ± 1.56), and the mean differences were statistically significant (p ≤ 0 05). A statistically significantly higher total antioxidant capacity (116.78 ± 5.03 Trolox Eq/L) was obtained in the post-surgery than pre-surgery level (79.65 ± 17.914 Trolox Eq/L) (p ≤ 0 05).

Conclusion

Higher oxidant and lower antioxidant levels were found in the serum of brain tumour patients than in the control group. The post-surgery oxidant level was lower than the pre-surgery state. The findings of this study could suggest that redox imbalance may have a role in the pathophysiology of brain tumours, but further experimental studies are needed.