Zika virus endemic challenges during COVID-19 pandemic in Africa

Application of mPEG-PCL-mPEG Micelles for Anti-Zika Ribavirin Delivery

Nanoparticles are rapidly becoming the method of choice for a number of nanomedicine applications, especially drug delivery. Many current nanoparticle models for drug delivery include a metal base with a drug conjugated to its surface. However, this raises concerns regarding toxicity since the conjugated drug and metal-based center of the nanoparticle are generally not biocompatible. A novel approach to solve this dilemma is the development of nanosized biocompatible polymer-based micellar nanoparticles (MNPs), created from methoxy poly(ethylene-glycol) poly(ɛ-caprolactone)-methoxy poly(ethylene glycol) (i.e., mPEG-PCL-mPEG) triblock polymers formed around an antiviral drug of choice, ribavirin. The goal is to create a drug carrier triblock nanoparticle system that is labile at a specific intercellular pH resulting in drug release, leading to the suppression of viral pathogens, and without undue toxicity to the cell. Through this approach we created a drug-loaded nanoparticle that dissociates when exposed to pH of 5.49 (endosomal pH), releasing ribavirin intercellularly, resulting in effective suppression of the mosquito-borne virus, Zika, in JEG-3 cells (gestational choriocarcinoma cells), in comparison to untreated and unencapsulated ribavirin controls as shown by plaque reduction assays and confirmation by RT-PCR. The level of suppression observed by ribavirin-loaded MNPs was achieved while requiring approximately 90% less ribavirin than in experiments utilizing unencapsulated ribavirin. The drug delivery system that is described here has shown significant suppression of Zika virus and suggests a role for this drug delivery system as an antiviral platform against additional viral pathogens.

Sustained chronic inflammation and altered childhood vaccine responses in children exposed to Zika virus

BACKGROUND

Congenital Zika virus (ZIKV) infection leads to severe newborn abnormalities, but its long-term impact on childhood immunity is not well understood. This study aims to investigate the serum proteomics in children exposed to ZIKV during pregnancy to understand potential immunological consequences during early childhood.

METHODS

The study included ZIKV-exposed infants (ZEI) at birth (n = 42) and children exposed to ZIKV (ZEC) at two years of age (n = 20) exposed to ZIKV during pregnancy, as well as healthy controls. Serum proteomic analysis was performed on these groups to assess inflammation and immune profiles. Additionally, antibody titres against two common childhood vaccines, DTaP and MMR, were measured in healthy controls (n = 50) and ZEC (n = 92) to evaluate vaccine-induced immunity.

FINDINGS

Results showed elevated inflammation in ZEI with birth abnormalities. Among ZEC, despite most having normal clinical outcomes at two years, their serum proteomics indicated a bias towards Th1-mediated immune responses. Notably, ZEC displayed reduced anti-Diphtheria toxin and anti-Clostridium tetani IgG levels against DTaP and MMR vaccines. They also exhibited lower antibody titres particularly against Th2-biased DTaP vaccines, but not Th1-biased MMR vaccines.

INTERPRETATION

In conclusion, the study highlights the long-term immunological consequences of congenital ZIKV exposure. Heightened inflammation was observed in ZEI with abnormalities at birth, while ZEC maintained a chronic Th1-biased immune profile. The impaired response to Th2-biased vaccines raises concerns about lasting effects of ZIKV exposure on immune responses. Consequently, there is a need for continued longitudinal clinical monitoring to identify potential immune-related complications arising from prenatal exposure to ZIKV.

FUNDING

This work was partially funded by the National Institute of Allergy and Infectious Diseases (NIAID) and National Institute of Dental and Craniofacial Research (NIDCR).

Malaria vaccine: The lasting solution to malaria burden in Africa

Malaria is one of the deadliest infectious diseases in Africa. Many measures have been taken over the past few years to reduce the burden of malaria on public health following the recommendation of WHO, still, malaria has continued to rake devastation in Africa. Combating malaria in Africa has grown into an international concern. The eradication of malaia is a long-standing goal of public health initiatives globally. The development of vaccines will go a long way to provide the required immunity needed for the people living with malaria or vulnerable to malaria. It is imperative that a vaccine should be produced and rolled out for use, especially during the time of the COVID-19 pandemic when attention is given to mitigating the impact of the pandemic on public health. The malaria vaccine will reduce the number of hospital admission for malaria illness among children and other age groups. Africa will need to build strong innovations to overcome country-specific challenges in vaccination drive, human resources, and supply chain management. Accelerating education, sensitization, diagnosis, and eradication through joint efforts of the government, healthcare professionals and general population will help to prevent the dual synchronous epidemic of COVID-19 and Malaria in Africa.

Vector-Borne Diseases amidst COVID-19 Pandemic in India - A Mini-Review

Introduction:Vector-borne diseases are infections caused by parasites, viruses and bacteria and transmitted by vectors, which are usually insects. A greater risk of diseases such as dengue, malaria, seasonal influenza, leptospirosis, chikungunya, enteric fever, etc co-exist in COVID-19 cases. This poses challenges in clinical and laboratory diagnosis of COVID-19, which may affect clinical management and patient outcomes. Methodology: Several databases, including PubMed, Scopus, DOAJ, and EMBASE, were reviewed using the keywords vector-borne infections in India amidst COVID-19 pandemic. A total of 23 articles and WHO and National website for vector-borne diseases was found. Review:For many decades, vector-borne diseases have been a major health burden for both underdeveloped and developing countries, including India. With better preparedness, the threat of climate change on vector-borne diseases may be negated. Rains during monsoon increase not only the risk of vector-borne diseases such as malaria, dengue, chikungunya but also that of food- and water-borne diseases as well as other skin infections. A greater risk of diseases such as dengue, malaria, seasonal influenza, leptospirosis, chikungunya, enteric fever, etc co-exists in COVID-19 cases. This poses challenges in clinical and laboratory diagnosis of COVID-19, which may affect clinical management and patient outcomes (3). Amidst the COVID-19 pandemic, a sudden outbreak of Zika virus infection was reported at the beginning of July 2021 in the districts of Kerala, from where it started, spreading to the neighboring states of Tamil Nadu and Kerala, India. Conclusions:With better preparedness, the threat of climate change on vector-borne diseases may be negated. Designing and strengthening an intervention strategy for environmental sanitation, regular cleaning of living houses, and keeping personal hygiene shall be considered. Risk assessment is crucial to optimize surveillance, preventative measures (vector control), and resource allocation (medical supplies).