Brief Answer:
No risk of HIV

Detailed Answer:
Hi,

Thanks for choosing health care magic for your query.

I understand your concern of getting exposed to HIV.

The risk of exposure is high when exposed to infected fluid most commonly blood and genital secretions than other body fluids.

The urine, feces, sweat, bronchoalveolar secretions, amniotic fluid, synovial fluid and milk have been reported to have zero or few HIV particles and therefore these secretions are not important sources of infection.

Based on the details provided in your query, I can assure you that you have no risk of acquiring HIV by just sharing a straw with a person whose HIV status is not known.

Moreover, the saliva also contains non specific inhibitory substances like fibronectin which prevents cell to cell transfer of virus.

Thus saliva is not likely vehicle of HIV transmission.

Please quit worrying unnecessarily.

I hope I have cleared your doubts.

Please let me know if I can assist you further.

Thanks.

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