Persistence of vaccine-derived poliovirus following a mass vaccination campaign in Cuba: implications for stopping polio vaccination after global eradication.
BACKGROUND
With substantial progress made toward polio eradication, developing the appropriate strategy for discontinuing global oral poliovirus vaccine (OPV) after global eradication becomes increasingly important. At issue is the theoretical risk of independent circulation of potentially virulent OPV-derived strains. Because Cuba uses OPV only in mass campaigns, it represents an ideal site to assess vaccine-derived poliovirus persistence.


METHODS
Infants born after the 1997 biannual mass campaigns were evaluated for past (neutralizing antibody) or current (virus excretion) evidence of vaccine-derived poliovirus exposure. We obtained sera and/or stool specimens from 861 infants; a second serum from 218 infants.


RESULTS
All stool specimens were poliovirus negative. Of 762 infants, 113 (14.8%) had initially detectable poliovirus type 1 antibody, 193 (25.3%) type 2, and 94 (12.3%) type 3. A precipitous antibody decline occurred in initially positive sera.


CONCLUSIONS
Our results suggest that in a country with high population immunity, vaccine-derived virus is unlikely to establish ongoing circulation.
Más Lago
P
P
Pedro Kouri Institute for Tropical Medicine, Havana, Cuba. pmasl@ipk.sld.cu
Cáceres
V M
VM
Galindo
M A
MA
Gary
H E
HE
Valcarcel
M
M
Barrios
J
J
Sarmiento
L
L
Avalos
I
I
Bravo
J A
JA
Palomera
R
R
Bello
M
M
Sutter
R W
RW
Pallansch
M A
MA
de Quadros
C A
CA
D003462:Cuba / Q000453:epidemiology; D014943:Global Health; D006801:Humans; D017589:Immunization Programs; D007223:Infant; D007231:Infant, Newborn; D011051:Poliomyelitis / Q000453:epidemiology / Q000517:prevention & control*; D011055:Poliovirus Vaccine, Oral
D011055:Poliovirus Vaccine, Oral