The article discusses the potential of chloroquine, an old drug known since 1934, to address modern viral infections such as AIDS and severe acute respiratory syndrome (SARS). Chloroquine has been found to have antiviral and immunomodulatory effects, making it a promising candidate for treating viral diseases. The drug can inhibit the replication of various viruses, including flaviviruses, retroviruses, and coronaviruses, by affecting the endosome-mediated viral entry or late stages of replication. Additionally, chloroquine reduces the production of proinflammatory cytokines like tumor necrosis factor α (TNFα) and interleukin 6 (IL6), which are often associated with viral infections and can exacerbate symptoms. Clinical trials have shown that chloroquine can reduce HIV-1 RNA levels and decrease the secretion of proinflammatory cytokines. The drug's safety profile is well-established, with limited toxicity, and it may be particularly useful in resource-poor settings. The article also explores the potential of chloroquine in preventing mother-to-child transmission of HIV through breastfeeding and in managing SARS, where it could help control the inflammatory response. Overall, the authors suggest that further research is needed to fully understand the drug's potential in treating viral infections.The article discusses the potential of chloroquine, an old drug known since 1934, to address modern viral infections such as AIDS and severe acute respiratory syndrome (SARS). Chloroquine has been found to have antiviral and immunomodulatory effects, making it a promising candidate for treating viral diseases. The drug can inhibit the replication of various viruses, including flaviviruses, retroviruses, and coronaviruses, by affecting the endosome-mediated viral entry or late stages of replication. Additionally, chloroquine reduces the production of proinflammatory cytokines like tumor necrosis factor α (TNFα) and interleukin 6 (IL6), which are often associated with viral infections and can exacerbate symptoms. Clinical trials have shown that chloroquine can reduce HIV-1 RNA levels and decrease the secretion of proinflammatory cytokines. The drug's safety profile is well-established, with limited toxicity, and it may be particularly useful in resource-poor settings. The article also explores the potential of chloroquine in preventing mother-to-child transmission of HIV through breastfeeding and in managing SARS, where it could help control the inflammatory response. Overall, the authors suggest that further research is needed to fully understand the drug's potential in treating viral infections.