Trends in resistance to penicillin and erythromycin of invasive pneumococci in Portugal.
Antimicrobial resistance of pneumococci is influenced by serotypes, antimicrobial consumption and vaccine use. Serotyping of 697 out of 1331 pneumococcal isolates, recovered in Portugal from 1994 to 2004, showed that the theoretical rate of heptavalent conjugate vaccine coverage was 91.7% and 63.6% for penicillin and erythromycin non-susceptible strains, respectively, in children up to 1 year old. The use of amoxicillin and erythromycin decreased in the vaccine period 2001-2004 (P=0.04 and P<0.01, respectively) but azithromycin usage increased in the same period (P<0.01). By using linear regression models, we evaluated the role of antimicrobial and vaccine use in the trends of resistance to penicillin and erythromycin among the isolates. The models suggest that the use of macrolides was the main factor associated with an increase of penicillin and erythromycin non-susceptible isolates from adults (P<0.01) and erythromycin non-susceptible isolates among children (P=0.006). These models also suggest that heptavalent vaccine is failing to reduce antimicrobial resistance as expected, possibly due to the increased consumption of azithromycin (P=0.04). The efficient use of new antibiotics may reverse the present trends of antimicrobial resistance.
Dias
R
R
Antibiotic Resistance Unit, Centre of Bacteriology, National Institute of Health, Dr Ricardo Jorge, Lisbon, Portugal.
Caniça
M
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000658:Amoxicillin / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D017963:Azithromycin / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D024881:Drug Resistance, Bacterial; D004917:Erythromycin / Q000494:pharmacology* / Q000627:therapeutic use; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D018942:Macrolides / Q000627:therapeutic use; D022401:Meningococcal Vaccines / Q000276:immunology; D008875:Middle Aged; D015233:Models, Statistical; D010406:Penicillins / Q000494:pharmacology*; D011008:Pneumococcal Infections / Q000382:microbiology*; D022242:Pneumococcal Vaccines / Q000276:immunology; D011174:Portugal; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification / Q000187:drug effects* / Q000302:isolation & purification
D000900:Anti-Bacterial Agents; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D018942:Macrolides; D022401:Meningococcal Vaccines; D010406:Penicillins; D022242:Pneumococcal Vaccines; D004917:Erythromycin; D000658:Amoxicillin; D017963:Azithromycin
Clin Infect Dis. 2000 Oct;31(4):875-80
11049764
Antimicrob Agents Chemother. 2006 Jun;50(6):2098-105
16723571
J Antimicrob Chemother. 2001 Oct;48(4):463-78
11581224
Pediatr Infect Dis J. 2001 Oct;20(10):951-8
11642629
Infection. 2001 Oct;29(5):251-6
11688901
Emerg Infect Dis. 2002 Mar;8(3):278-82
11927025
J Antimicrob Chemother. 2002 Oct;50(4):611-2
12356811
Clin Microbiol Infect. 2002;8 Suppl 2:12-42
12427206
J Antimicrob Chemother. 2002 Dec;50 Suppl S2:1-5
12556427
J Antimicrob Chemother. 2002 Dec;50 Suppl S2:27-37
12556431
J Antimicrob Chemother. 2002 Dec;50 Suppl S2:39-43
12556432
J Antimicrob Chemother. 2003 Feb;51(2):409-14
12562712
N Engl J Med. 2003 May 1;348(18):1737-46
12724479
Lancet Infect Dis. 2004 Mar;4(3):144-54
14998500
J Antimicrob Chemother. 2004 May;53(5):793-6
15056640
Antimicrob Agents Chemother. 2004 Jun;48(6):2206-13
15155223
Antimicrob Agents Chemother. 2004 Aug;48(8):2883-7
15273096
Curr Drug Targets Infect Disord. 2004 Sep;4(3):203-6
15379731
Rev Infect Dis. 1981 Mar-Apr;3(2):246-53
7020043
BMJ. 1996 Aug 17;313(7054):387-91
8761224
J Clin Microbiol. 1997 Mar;35(3):764-6
9041430
Pediatr Infect Dis J. 1997 Apr;16(4):438-43
9109156
Proc Natl Acad Sci U S A. 1997 Jun 10;94(12):6571-6
9177259
Int J Med Microbiol. 2004 Oct;294(5):277-94
15532987
J Antimicrob Chemother. 2004 Dec;54(6):1035-9
15531597
J Antimicrob Chemother. 2004 Dec;54(6):1045-50
15531598
Acta Med Port. 2004 Jan-Feb;17(1):49-53
15636727
Lancet. 2005 Feb 12-18;365(9459):579-87
15708101
Pediatr Infect Dis J. 2005 Mar;24(3):243-52
15750461
Emerg Infect Dis. 2005 Jun;11(6):829-37
15963276
Antimicrob Agents Chemother. 2005 Aug;49(8):3520-2
16048973
Antimicrob Agents Chemother. 2006 Jun;50(6):2064-71
16723567
Lancet. 2001 Jun 9;357(9271):1851-3
11410197