Biology is usually the first science high school students are taught because it has less of a focus on math than other science subjects, so freshman have time to develop their math skills before moving on to more math-focused sciences.
HIV can be transmitted from an HIV-positive woman to her child either during pregnancy, or during labour and delivery, or by breastfeeding.In Europe and the USA, about 15 to 20% of babies born to HIV-positive women who are not taking anti-HIV drugs are infected.IV can be transmitted from an HIV-positive woman to her child either during pregnancy, or during labour and delivery, or by breastfeeding.
There's a period of time after a person is infected during which they won't test positive. This is called the HIV window period.. The window period can be from 10 days to 3 months, depending on the person's body and on the HIV test that's used. During that time, you can test HIV-negative even though you're HIV-positive. You can still get HIV from someone who is in the window period.