Table 1

 Examples of HHV-6 and -7 antibody responses and detection of DNA in primary infections

Nature of infection*Example: patient no.Days after admission sample takenPlasma or serum
HHV-6 IgGHHV-6HHV-7 IgGHHV-7
TitreAvidityDNATitreAvidityDNA
*The criteria for primary and past infection, and uninfected are described in the Methods.
†Patient 20 had primary HHV-7 infection pinpointed to the disease episode by the detection of HHV-7 DNA in the acute CSF rather than serum (Methods b).
‡Patient 14 was only 4 months old and HHV-6 IgG of high avidity was consistent with either persisting maternal antibody or past HHV-6 infection.
nt, not tested.
Dual primary HHV-6 and -7 infections (patients 1 and 2)21ntnt+<16nt–
2<16ntntntntnt
17 2048 Low nt 256 Low nt
Primary HHV-6 infection without HHV-7 infection (patients 3–12)60<16nt+<16nt–
4<16nt+<16nt–
10 2048 Low –ntnt–
55512Highnt<16ntnt
Primary HHV-6 infection with past HHV-7 infection (patient 13)13332nt+128High–
14 128 Low –128High–
Primary HHV-7 infection without HHV-6 infection (patients 15–22†)214<16nt–<16nt+
1116nt– 512 Low –
41<16ntnt 512 Low nt
1681 6nt–512High–
Primary HHV-7 infection with past HHV-6 infection (patients 14‡, 23–26)233512High– 64 Low +
158192Highnt 8192 Low nt
961024High– 4096 Low –
119512High–256Highnt