Causes of Low White Blood Cell Count

2. Viral Infections

Viral infections such as HIV can have an impact on white blood cell production, disrupting production and, thus, making it more difficult for the immune system to do its job. Opportunistic infections are those normally easily prevented but can cause illness in people with compromised immune systems, such as those with HIV and AIDS. Occasionally, even relatively common and minor respiratory viruses can make their way to the bone marrow, lowering the white blood cell count and making it harder for the body to defend itself.

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