Voorbeelden van seronegative

• All 28 children followed for 12 months became seronegative, thus excluding a congenital infection.

• This was the number of individuals that were seronegative when captured prior to that period and were recaptured after that period.

• The period of time it took for eight seropositive herds to become seronegative during the observation period varied from 2 to 22 months.

• Two approaches were taken to designate sera as seropositive or seronegative.

• In total, 341 (221 seronegative and 120 seropositive) students were followed up clinically and serologically during a subsequent outbreak.

• Six out of nine seronegative herds, which became seropositive, returned to their negative status after 3-7 months.

• Two control flocks per case were randomly selected from the flock population that was seronegative for 1997 and 1998 in the same province.

• Remitting seronegative, symmetrical synovitis with pitting edema - 13 additional cases.

• Fifty-four seropositive and 108 seronegative index children were included and 480 out of 548 family members contributed blood.

• On 21 occasions (18 %), growers were seronegative, while the finishers in the subsequent sampling round were seropositive.

• Potential detection of the seroconversion of an individual rabbit required that it be caught whilst seronegative and subsequently recaptured.

• For statistical analysis, negative and equivocal laboratory results were grouped together and classified as seronegative.

• The severity of illness and case-fatality ratios were observed to be more among seronegative individuals than seropositives during an epidemic.

• The proportion seronegative for diphtheria tended to increase with age such that 42 % of individuals aged >40 years were seronegative.

• The participation rate was 54/68 (79 %) for seropositive index children and 108/165 (65 %) for seronegative index children.