Serum samples were studied from the CAMERA cohort, a 2-year, multicentre, prospective, open-label study.
Non-fasting serum samples were studied because participants were convenience sampled from health care and community settings.
Only one serum sample for each pregnant woman was studied at each trimester, so a total of 770 serum samples were studied at the end of the study.
For each donor, 2 follow-up serum samples were studied, collected 1 year apart (T0 and T12).
Serum samples were studied by ELISA for WNV IgG and IgM (Focus), and positive results were obtained for IgG to WNV in both samples and for IgM in S1.
Serum samples were studied by using a hemagglutination inhibition (HI) assay against 2 recently circulating swine strains, A/Swine/WI/238/97 (H1N1) and A/Swine/WI/R33F/01 (H1N2), and 1 human influenza virus strain, A/New Caledonia/20/99 (H1N1).
In the fourth group, a single serum sample was studied from each of 168 randomly selected Fort Dix basic trainees who had received their annual influenza vaccination 3 to 4 weeks earlier (11 ).
Goat serum samples were collected in field studies carried out in various countries without ethics committees (e.g., Tajikistan and Afghanistan).
Serum samples were obtained on study day 14 prior to vaccinations and at 14 and 28 days after the vaccinations (study days 28 and 42, respectively).
Serum samples were analyzed on study admission (early; day 1) and late (either day 3, 4 or 5) where available.
