Jpn. J. Infect. Dis., 54, 2001

Laboratory and Epidemiology Communications

Prevalence ofAdenovirus Types 3 and 7 Antibodies in Singapore
Osamu Nishio*,Kiyohiko Matsui, Kee‑tai Goh. , Yasuko Matsunaga2and Sakae Inouye2･3
Departmen i of Microbiology, National Institute of Public Health,
Shirokanedai 4‑611, Minato‑ku, TobJo 108‑8638,
IQuarantine & Epidemiology Department, Minisり′ of the Environment, Singapore,

21nfectious Disease Surveillance Centef; National Institute of lnfectious Diseases, TTob}o and30tsuma women i UniversiO?, Too,oCommunicated by Sakae lnouye(Accepted August 2, 200 1 )Adenovims types 3 and 7 (Ad3 and Ad7), which belong toolds in the sera collected in 1993‑1994, indicatlng that thesubgenus 良 of human adenovirus, cause both acute kerato‑

conjunctivitis and resplratOry‑tract infections. Particularly,

people up to the age of40 had not experienced Ad7 infection
in1 993‑ 1 994. h contrast, we found that the Ad3 seroprevalence

Ad7 is known to elicit lethal pneumonia in children with abasal ailment in the heart or lung (1). In Japan, Ad7 began tothe prevalence curves rise up from the youngest age. Thus

curves are qulte Similar between the 1970s and the 1990S:

pediatricians because the number of Ad丁 isolation reports

we postulated that Ad7 had not prevailed in Japan since thelate 1950s or early 1960s while Ad3 had been present all theincreased during 1996‑ 1998 accompanying serious cases (4);time (5).

be isolated in 1995 (2,3) and it raised a great concem among

however, the isolation decreased in 1999 and 2000 (4).

In the present study, we conducted a serosuⅣey uslng Sera

To investlgate the epidemiology ofAd3 and Ad7 infections

collected in Singapore in 1 992 and compared the results within Japan, We previously conducted a retrospective serosuⅣey

those of Japan. We used sera collectedfrom 545 persons at(5) using sera stored in Serum Bank, National Institute of

the age of 1 to 69 years livlng in Singapore. Neutralizing

hfectiousDiseases, and fo血d that the Ad7 antibody‑prevalence

rates were less than lO% among <15‑year‑olds in the sera

antibodies to Ad3 and Ad7 were assayed with use of the HEp‑
2 cells, as previously described (5). Antibody titers of 1 :4 0r

collected in 1974‑1975 but they were low among <40‑year‑

over were regarded as antibody positive･

Figure 1 shows the age‑specific seroprevalence curves of*Co汀eSpOnding author: E‑mail: nishio@iph.go.jp

Ad3 and Ad7. Anti‑Ad7 prevalence rates were low among128

Jpn. J. Infect. Dis., 54, 2001

at ua^!) sodApoq!tuv′‑U 5 4 3 つム

00000

1‑2

3‑6Nooftestedscra(97)

7‑10(134)

11‑15(48)

16‑19(31)

20‑29(23)30‑39(68)

40‑49(78)

50‑69(38)yr(28)

Fig. L Prcvalcncc orNT antibody by age

Table 1. Geometric mean NT antibody titcrs (2n) by age
Age yr
1ー2anti‑Ad7anti‑Ad31(I)‑ (22)

3̲6‑(12)5.01(50)2

7‑10

一(3)

5.3(15)

1 I ‑1 5‑(4)16‑1 9‑(1)4.9(18)

20‑29

‑(6)

4.7(10)30‑392.9(25)4.2(41)40‑49

2.5(15)3.8(58)4.3(32)50‑69

2.9(13)4.0(25)

I : Mean NT antibody liters are calculated when antibody positive rates are above 25% in each age group.
2 : positiye cases.

1982. Morbid. Mortal. Wkly. Rep., 32, 258‑260.

<30‑yearl01ds, whereas anti‑Ad3 prevalence increased from

2. National Institute of Health and Infectious Diseases

the youngest age. Table I shows geometric mean antibody

titers among antibody positives in different age groups･ Ad3

ControI Division, Ministry of Health and Welfare ( 1 996):

antibody titers in young age groups were higher than those in

Emergence ofadenovirus type 7, Japan, 1995･ Infect･

older age groups; Ad7 antibody titers among ≧30‑year‑olds

Agents SuⅣeillance Rep･, 17, 99'‑100'･

were low (22･5 to 22 9). These results were fわund to be similar

3. Yamadera, S., Yamashita, K., Akatsuka, M., Kato, N. andto the antibody prevalence pattems and mean antibody titers

Inouye, S. (1998): Trend ofadenovirus type 7 infection,of the sera collected in 1982‑1983 in Japan (5).

an emerglng disease. Jpn. ∫. Med. S°i. Bio1., 51, 4ト49･

The above seroepidemiologic data suggest that the Ad7

4. National Institute of Infectious Diseases and Infectious

infection had not been endemic for a few decades in Singapore

Diseases Control Division, Ministry or Health andWelfare (2000): Adenoviruses, I 9951 1 999. Infect. Agentsbefわre the time of the semm collection (1 992), although Adワ

was sporadically isolated in the 1980S (6)･ Recentlyfrom 1994,
however, at Singapore General Hospital, some numbers ofSuⅣeillance Rep., 21, 24'‑25'.

Adワ have been isolated (7). Once Ad7 is introduced into

5. Nishio, 0., Matsui, K., Akiyama, M., Nanbu, M., Oka, T.,
Matsunaga, Y and houye, S. (1998): Change in antibody

Singapore, it may spread among non‑immune young people.

prevalence to adenovirus type 7 during the past 20 years

A close watch is needed in order to prevent Ad7 nosocomial

in Japan. Clin. Ⅵrol･, 26, 255‑259 (in Japanese)･

6. Doraisingham, S. and Ling, A.E. (1986): Pattems ofviral
resplratOry tract infection in Singapore･ Ann･ Acad･ Med･,

infections in pediatric wards.

15, 9‑14.

REFERENCE S

7. Department of Pathology, Singapore General Hospital(1 98612000): Annual Reports.

1. Centers fわr Disease Control (1983): Adenovirus type 7

0utbreak in a pediatric chronic‑care facility‑Pennsylvania,

129