Addressing the Challenge of HIV Detection: Navigating the Lengthy Window Period in Malaysia
By Dr Low Bin Seng
Human immunodeficiency virus (HIV) is a virus that attacks the body’s immune system, leading to acquired immunodeficiency syndrome (AIDS) in advanced stages. HIV targets the body’s white blood cells, weakening the immune system and making individuals more vulnerable to diseases like tuberculosis, infections, and certain cancers.
In Malaysia, HIV remains a significant public health concern, with thousands living with the virus and many more at risk of transmission. According to Joint United Nations Programme on HIV/AIDS (UNAIDS) statistics for 2023, there were 85,000 people, including both adults and children, living with HIV in Malaysia. Of these, 2,900 were newly infected within the year. This highlights the ongoing need for effective prevention, diagnosis, and treatment initiatives.
HIV Transmission and Prevention
HIV is transmitted through body fluids such as blood, breast milk, semen, and vaginal secretions, as well as through unsafe medical procedures or needle injuries. It cannot spread through casual contact like kissing, sharing food or water. While there is no cure, HIV can be effectively managed with antiretroviral therapy (ART), enabling people with HIV to lead long lives. Early ART access and adherence are crucial to health improvement and preventing transmission. In Malaysia, the most common HIV test detects antibodies, which typically appear within 28 days of infection. However, during the “window period” when antibodies are undetectable, individuals may still transmit HIV, posing challenges for accurate diagnosis and blood transfusion safety.
The Challenge of the Window Period in HIV Detection
The “window period” presents a unique challenge in HIV detection, both globally and in Malaysia. During this time, an individual infected with HIV may not have produced antibodies, and thus, HIV tests may give false negative results – leading to a false sense of security.
In Malaysia, routine HIV testing is offered through the Ministry of Health’s public health clinics, but many people may not realise the importance of early detection or fail to test during the window period. The window period varies based on the type of test used:
• Antibody Tests: These tests detect antibodies produced by the immune system in response to HIV. The window period for antibody tests is typically 3 to 12 weeks after exposure.
• Antigen/Antibody Tests: These tests can detect both HIV antibodies and antigens (specifically the p24 antigen). The window period is usually 2 to 6 weeks.
• Nucleic Acid Tests (NATs): These tests detect the virus itself. The window period for NATs is about 1 to 4 weeks.
These tests are widely available, with public clinics providing low-cost testing options. However, ensuring that high-risk groups are regularly tested remains a challenge, as many individuals in these groups may not seek testing due to stigma or lack of awareness.
Challenges Posed by the Window Period
• Delayed Diagnosis: Individuals who are recently infected may not be aware of their status and could unknowingly transmit the virus to others during the window period, especially in high-risk groups who do not have access to regular screening.
• Psychological Impact: The uncertainty and anxiety of not knowing one’s HIV status can discourage individuals from getting tested, especially in conservative communities.
• Public Health Implications: Unaware individuals who test negative during the window period may not take precautions, contributing to the spread of HIV.
• False Negatives: False-negative results during the window period can delay appropriate interventions and treatment, making it more challenging to manage HIV effectively.
Strategies to Mitigate Challenges in Malaysia
• Education and Awareness: Increasing public awareness campaigns, like those led by Malaysia’s National AIDS Control Programme (NACP), are critical to educate about the window period and the importance of regular testing, especially after potential exposure to help mitigate the risks associated with false negatives.
• Combination Testing: Using a combination of different types of tests (e.g., antibody tests and antigen/antibody tests) can help reduce the likelihood of false negatives and improve early detection rates, particularly in high-risk populations.
• Regular Screening: Encouraging regular HIV screening is vital, especially for high-risk groups such as individuals who inject drugs and sex workers. This can be facilitated through community health outreach programmes.
• Pre-Exposure Prophylaxis (PrEP): The Malaysian government has started to make PrEP available to individuals at high risk, helping reduce the likelihood of HIV transmission. Continued efforts to increase access to PrEP will be essential in curbing new infections.
As we observe World AIDS Day on December 1st globally, we must remain committed to strengthen efforts in HIV testing and prevention, focusing on innovative solutions to address the “window period”. By recognising these challenges and implementing effective strategies, we can raise awareness about HIV, improve access to ART for early detection, expand testing technologies, reduce transmission, and provide timely support to those affected. These actions are vital to Malaysia’s progress towards better HIV management, prevention and the elimination of the stigma surrounding the disease.
Dr Low Bin Seng is an Associate Professor at the School of Medicine, Faculty of Health and Medical Sciences, Taylor’s University.