BIO 212 Final Project Guidelines and Rubric

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5-3 Final Project Milestone Two: Disease Pathology, Management, and Pharmacological Impact Summary

Rotavirus

Rotavirus is a non-enveloped, double-stranded RNA virus belonging to the family Sedoreoviridae with a triple-layered icosahedral capsid. It has 11 segments of the genome that encode structural proteins, which facilitate viral attachment and entry into host cells. It contains a nonstructural protein that is an enterotoxin and causes diarrhea (Omatola & Olaniran, 2022). Identification is performed by enzyme immunoassay (EIA) or rapid immunochromatographic testing, and the genotyping is done using RT-PCR (Pawluszkiewicz et al., 2025).

Rotavirus penetrates the enterocytes of the small intestine via an endocytosis process involving receptors. Viral replication takes place in the cytoplasm in viroplasms once inside. The protein moves to the nucleus of the host cell, blocking interferon signaling and breaking nuclear bodies, which suppress the antiviral response in the host and contribute to the establishment of a persistent infection. Another protein causes chloride secretion, tight junction disruption, makes the gut leaky, flooded with fluid, which disrupted nutrient absorption and resulted in diarrhea (Pawluszkiewicz et al., 2025).

Rotavirus infection clinically manifests itself with profuse watery diarrhea, vomiting, low-grade fever, and dehydration, which, as a rule, occurs 1-3 days after exposure. These are symptoms that direct diagnosis, and treatment is geared towards rehydration either orally or intravenously to avoid shock (Varghese & Kang, 2022).

The mainstay of treatment for rotavirus includes oral rehydration therapy (ORT) and intravenous fluids in severe cases. These measures help restore fluid balance, reduce complications, and improve patient outcomes, particularly in vulnerable populations such as infants (Pawłuszkiewicz et al., 2025). Pharmacological options are limited, but nitazoxanide has demonstrated efficacy in shortening the duration of symptoms by inhibiting viral replication (Jiang et al., 2023).

Nitazoxanide works by disrupting viral morphogenesis in the cytoplasm, without involving the nucleus, to limit viral spread (Pawłuszkiewicz et al., 2025). Preventive strategies include widespread use of vaccines such as Rotarix and RotaTeq, which reduce severe disease by 85–95%. Other preventive measures, including hand hygiene, surface disinfection, and public education, further reduce transmission (Varghese & Kang, 2022).

Methicillin-Resistant Staphylococcus aureus (MRSA)

MRSA is a gram-positive coccus that carries the mecA gene, which encodes an altered penicillin-binding protein, conferring resistance to beta-lactam antibiotics. Additionally, MRSA produces virulence factors, which promote tissue damage and immune evasion (Popovich et al., 2023). MRSA is diagnosed through culture of clinical specimens followed by coagulase testing and PCR for the mecA gene (Popovich et al., 2023).

MRSA colonizes the skin and nasal passages, entering the body through breaks in the skin. As a prokaryote, MRSA does not enter the host cell nucleus or use nuclear machinery. Instead, it replicates extracellularly via binary fission, releasing toxins that cause tissue necrosis, abscess formation, and immune system evasion. The ability of MRSA to form biofilms complicates treatment and contributes to its persistence (Popovich et al., 2023).

The MRSA infection may cause localized skin infections and severe illnesses, including pneumonia and bacteremia, which may lead to hypotension, sepsis, and organ failure (Popovich et al., 2023).

MRSA infection is treated using intravenous antibiotics, with vancomycin being the first-line agent in severe cases. The nonpharmacological approaches involve abscess incision and drainage, wound care, and the removal of infected equipment (Popovich et al., 2023). These interventions treat the underlying causes of the infection and work to lessen the complications such as sepsis and enhance patient outcomes through a reduction in hospital stays.

Vancomycin is a glycopeptide that is active against MRSA because it has a bactericidal effect that prevents cell wall synthesis by binding itself to the bacterial wall of peptidoglycan. This is a vital mechanism of bacterial survival, especially in resistant strains (Popovich et al., 2023). Some preventive strategies such as hand hygiene, contact precautions, and decolonization strategies are needed to reduce the spread of MRSA. Such strategies reduce MRSA infections in hospitals significantly (Popovich et al., 2023)

References

Jiang, L., Tang, A., Song, L., Tong, Y., & Fan, H. (2023). Advances in the development of antivirals for rotavirus infection. Frontiers in Immunology, 14, Article 1041149. https://doi.org/10.3389/fimmu.2023.1041149

Omatola, C. A., & Olaniran, A. O. (2022). Rotaviruses: From pathogenesis to disease control—A critical review. Viruses, 14(5), 875. https://doi.org/10.3390/v14050875

Pawłuszkiewicz, K., Ryglowski, P. J., Idzik, N., Błaszczyszyn, K., Kucharczyk, E., Gaweł-Dąbrowska, D., & Paluch, E. (2025). Rotavirus infections: Pathophysiology, symptoms, and vaccination. Pathogens, 14(5), 480. https://doi.org/10.3390/pathogens14050480

Popovich, K. J., Aureden, K., Ham, D. C., Harris, A. D., Hessels, A. J., Huang, S. S., Maragakis, L. L., Milstone, A. M., Moody, J., Yokoe, D., & Calfee, D. P. (2023). SHEA/IDSA/APIC practice recommendation: Strategies to prevent methicillin-resistant Staphylococcus aureus transmission and infection in acute-care hospitals: 2022 update. Infection Control & Hospital Epidemiology, 44(7), 1039–1067. https://doi.org/10.1017/ice.2023.102

Varghese, T., & Kang, G. (2022). Understanding rotavirus vaccine efficacy and effectiveness in countries with high child mortality. Vaccines, 10(3), 346. https://doi.org/10.3390/vaccines10030346