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The acceptability and behavioral effects of antibiotic prophylaxis for syphilis prevention.

BACKGROUND AND OBJECTIVES: Use of preexposure antibiotic prophylaxis for syphilis control has been limited by concerns about acceptability and adverse behavioral effects. GOAL: The goal was to determine whether persons at high risk for syphilis accept antibiotic prophylaxis and if so, whether they subsequently increase their risky behavior. STUDY DESIGN: We gave a prospective cohort of persons either: 1) single doses of benzathine penicillin, azithromycin, and cefixime; or 2) a single dose of cefixime and 3 doses of azithromycin given biweekly. RESULTS: Of 268 persons approached, 186 (69%) agreed to participate, 174 were treated, and 125 (72%) were located for follow up. Four weeks and 4 months after enrollment, participants reported reductions in the number of sex partners. At 4 months, 1% had acquired gonorrhea, 5% had acquired chlamydia, and none had acquired syphilis. CONCLUSION: Antibiotic prophylaxis for syphilis was acceptable and not followed by increases in risky behavior. Larger trials of preexposure antibiotic prophylaxis of core group members to control syphilis outbreaks should be undertaken.

Adolescent↗

Antibiotic prophylaxis and open groin hernia repair.

Antibiotic prophylaxis is not routinely given for nonimplant, clean operations, although this view has recently been challenged. We have conducted a randomized multicenter, double-blind prospective trial to compare co-amoxiclav with placebo in 619 patients undergoing open groin hernia repair. Altogether 563 (91%) patients fulfilled the protocol; 283 received co-amoxiclav and 280 placebo. There was no difference between the groups in the number of patients receiving local or general anesthetic, the type of repair performed, the use of a subcutaneous fat suture, the type of skin closure used, the use of wound analgesia, or the use of a wound drain. Patients were given a card to return to the hospital in the event of their wound discharging or their needing to see their general practitioner. All patients were reviewed at approximately 6 weeks after operation. Fifty (8.9%) patients sustained a wound infection, 25 in the co-amoxiclav group and 25 in the placebo group. We conclude that antibiotic prophylaxis is of no benefit to patients undergoing open groin hernia repair.

Adult↗

The implementation of a surgical antibiotic prophylaxis program: the pivotal contribution of the hospital pharmacy.

BACKGROUND: Although surgical site infection rates have decreased with the prophylactic use of antibiotics, the inappropriateness of surgical antibiotic prophylaxis is still a worldwide problem. Various strategies have been used to address this problem. This study describes the implementation of a perioperative antibiotic prophylaxis protocol that emphasizes the contribution of the pharmacist. METHODS: A descriptive study design was used to evaluate the impact of the protocol on the appropriateness of prophylaxis in a private university hospital. The surgical antibiotic prophylaxis of all surgeries was evaluated for 1 month before and 1 month after the implementation of the protocol. RESULTS: The appropriateness of the indication for prophylaxis rose from 56.4% to 100% and that of the postoperative maintenance prophylactic antibiotics rose from 21.9% to 95.7%. The cost of the perioperative antibiotic prophylaxis per surgery decreased 40.5%. CONCLUSION: The implementation of a cost-effective perioperative antibiotic prophylaxis protocol was the result of a multidisciplinary effort. The hospital pharmacist participated in education activities as part of the discussion groups on the perioperative antibiotic prophylaxis protocol that involved all participants and in managerial actions that optimized the process of ordering, dispensing, administering, and documenting the perioperative antibiotic prophylaxis.

Adolescent↗

Antibiotic prophylaxis in chemotherapy-induced neutropenia: time to reconsider.

The use of antibiotic prophylaxis in neutropenic patients remains controversial. The main arguments against prophylaxis are the lack of survival benefit and the risk of inducing antibiotic resistance. At present, clinical guidelines advise against routine use of antibiotic prophylaxis and current practice is to commence broad-spectrum antibiotics at the onset of fever in the neutropenic patient. However hospitalization, investigations and treatment all impact on resources as well as affecting patient quality of life, often resulting in chemotherapy delays and dose reductions. The benefits of prophylactic antibiotics have been emphasized by two major double-blind, placebo controlled trials with levofloxacin with very significant reductions in all infection-related events. Furthermore, the meta-analysis confirms a survival advantage and this is greatest with the use of fluoroquinolones. These benefits must be weighed against the problem of emerging antibiotic resistance. It has been shown that antibiotic prophylaxis does induce resistant organisms, but some studies have shown that the impact on clinical outcomes may not be as great as expected. Current evidence supports antibiotic prophylaxis with fluoroquinolones in acute leukaemia and high-dose chemotherapy patients, commencing at the same time as chemotherapy. Febrile episodes are much commoner with the first cycle in patients with solid tumours or lymphoma having moderately myelosuppressive chemotherapy, and these patients should be offered prophylaxis for at least the first cycle of chemotherapy. Further work is ongoing to facilitate the selection of patients with the greatest chance of benefit so that prophylaxis can be used efficiently.

Anti-Bacterial Agents↗

Long-term follow-up of children with vesicoureteral reflux with and without antibiotic prophylaxis.

The aim of the present study was to obtain data on the outcome of children with persistent vesicoureteral reflux (VUR) after cessation of antibiotic prophylaxis. Children with VUR who had been on antibiotic prophylaxis for at least 2 y and were free of urinary tract infections (UTI), had normal voiding patterns, and no hydronephrosis or new kidney scarring, had antibiotic prophylaxis discontinued, were followed up prospectively with urine cultures, voiding cystourethrography, and technecium-99m dimercaptosuccinate renal scintigraphy. The findings were compared with those of the same patients while they were on antibiotic prophylaxis. In 54 children (39 girls and 15 boys), antibiotic prophylaxis was discontinued. The mean follow-up time on and off antibiotic prophylaxis was 4.4+/-2.1 and 4.4+/-2.2 y, respectively. Nine UTI episodes occurred during the on- and 8 during the off-prophylaxis period. In 80 of 96 and in 68 of 74 ureters the reflux resolved or downgraded during the on- and off-prophylaxis periods, respectively. No new scar lesions were detected in any of the children. In conclusion, in children with persistent VUR and certain characteristics, antibiotic prophylaxis can be safely discontinued.

Anti-Bacterial Agents↗

Risk factors for adult nosocomial meningitis after craniotomy: role of antibiotic prophylaxis.

OBJECTIVE: To evaluate incidence and risk factors of postoperative meningitis, with special emphasis on antibiotic prophylaxis, in a series of 6243 consecutive craniotomies. METHODS: Meningitis was individualized from a prospective surveillance database of surgical site infections after craniotomy. Ventriculitis related to external ventricular drainage or cerebrospinal fluid shunt were excluded. From May 1997 until March 1999, no antibiotic prophylaxis was prescribed for scheduled, clean, lasting less than 4 hours craniotomies, whereas emergency, clean-contaminated, or long-lasting craniotomies received cloxacillin or amoxicillin-clavulanate. From April 1999 until December 2003, prophylaxis was given to every craniotomy. Independent risk factors for meningitis were studied by a multivariate analysis. Efficacy of antibiotic prophylaxis in preventing meningitis was studied as well as consequences on bacterial flora. RESULTS: The overall meningitis rate was 1.52%. Independent risk factors were cerebrospinal fluid leakage, concomitant incision infection, male sex, and surgical duration. Antibiotic prophylaxis reduced incision infections from 8.8% down to 4.6% (P < 0.0001) but did not prevent meningitis: 1.63% in patients without antibiotic prophylaxis and 1.50% in those who received prophylaxis. Bacteria responsible for meningitis were mainly noncutaneous in patients receiving antibiotics and cutaneous in patients without prophylaxis. In the former, microorganisms tended to be less susceptible to the prophylactic antibiotics administered. Mortality rate was higher in meningitis caused by noncutaneous bacteria as compared with those caused by cutaneous microorganisms. CONCLUSION: Perioperative antibiotic prophylaxis, although clearly effective for the prevention of incision infections, does not prevent meningitis and tends to select prophylaxis resistant microorganisms.

Adult↗

Prospective, randomised study on antibiotic prophylaxis in colorectal surgery. Is it really necessary to use oral antibiotics?

BACKGROUND AND AIMS: The use of prophylactic antibiotics in addition to mechanical cleansing is the current standard of care prior to colonic surgery. The question of whether the antibiotics should be administered intravenously or orally, or by both routes, remains controversial. Our aim was to compare three methods of prophylactic antibiotic administration in elective colorectal surgery. METHODS: Three hundred consecutive elective colorectal resections were studied. All patients had preoperative mechanical colon cleansing with oral sodium phosphate and intravenous antibiotic prophylaxis with cefoxitin (one dose before skin incision and two postoperative doses). Patients were randomised to one of the following three groups: group A: three doses of oral antibiotic (neomycin and metronidazole) at the time of mechanical colon cleansing; group B: one dose of oral antibiotic; group C: no oral antibiotics. All patients were followed during their hospital stay and at 7, 14 and 30 days post-surgery. RESULTS: Vomiting occurred in 31%, 11% and 9% of the studied patients (groups A, B and C, respectively) (p<0.001). Nausea was present in 44%, 18% and 13% of patients (p<0.001). Abdominal pain was recorded in 13%, 10% and 4% of patients (p: 0.077). Wound infection was present in 7%, 8% and 6% and suture dehiscence occurred in 2%, 2% and 3% of the patients in the three groups (no differences among them). Neither were differences found among the three groups in terms of urinary infections, pneumonia, postoperative ileus or intra-abdominal abscess. CONCLUSION: The addition of three doses of oral antibiotics to intravenous antibiotic prophylaxis is associated with lower patient tolerance in terms of increased nausea, vomiting and abdominal pain, and has shown no advantages in the prevention of postoperative septic complications. Therefore, we recommend that oral antibiotics should not be used prior to colorectal surgery.

Administration, Oral↗

Antibiotic prophylaxis in dermatologic surgery: updated guidelines.

BACKGROUND: Antibiotic prophylaxis in dermatologic surgery is poorly understood, and data on its use are lacking. Prophylaxis is indicated for the prevention of endocarditis and prosthesis infection, as well as surgical site infection. OBJECTIVE: We review essential considerations for the use of antibiotic prophylaxis in dermatologic surgery and provide clear guidelines for practical implementation. METHODS: Guidelines were developed after review of the literature and consultation with infectious disease specialists and subspecialists in the areas of cardiac, orthopedic, and neurosurgical infectious disease at Mayo Clinic. RESULTS: Three factors affect the decision to use prophylactic antibiotics in dermatologic surgery: (1) the underlying indication for prophylaxis (patient risk stratification), (2) the condition of the skin, and (3) the specific procedure planned. Thorough preoperative evaluation and surgical planning are critical in identifying and optimizing patient and environmental risk factors that may increase the risk of infection. Appropriate antibiotic selections with site-specific consideration and appropriate timing of antibiotic administration are key factors in providing effective prophylaxis. CONCLUSIONS: Low rates of infection associated with dermatologic surgical procedures warrant selective use of antibiotic prophylaxis. The proposed guidelines reflect current standards of practice.

Antibiotic Prophylaxis↗

Risk of surgical site infection and efficacy of antibiotic prophylaxis: a cohort study of appendectomy patients in Thailand.

BACKGROUND: No data currently exist about use of antibiotics to prevent surgical site infections (SSI) among patients undergoing appendectomy in Thailand. We therefore examined risk factors, use, and efficacy of prophylactic antibiotics for surgical site infection SSI among patients with uncomplicated open appendectomy. METHODS: From July 1, 2003 to June 30, 2004 we conducted a prospective cohort study in eight hospitals in Thailand. We used the National Nosocomial Infection Surveillance (NNIS) system criteria to identify SSI associated with appendectomy. We used logistic regression analysis to obtain relative risk estimates for predictors of SSI. RESULTS: Among 2139 appendectomy patients, we identified 26 SSIs, yielding a SSI rate of 1.2 infections/100 operations. Ninety-two percent of all patients (95% CI, 91.0-93.3) received antibiotic prophylaxis. Metronidazole and gentamicin were the two most common antibiotic agents, with a combined single dose administered in 39% of cases. In 54% of cases, antibiotic prophylaxis was administered for one day. We found that a prolonged duration of operation was significantly associated with an increased SSI risk. Antibiotic prophylaxis was significantly associated with a decreased risk of SSI regardless of whether the antibiotic was administered preoperatively or intraoperatively. Compared with no antibiotic prophylaxis, SSI relative risks for combined single-dose of metronidazole and gentamicin, one-day prophylaxis, and multiple-day antibiotic prophylaxis were 0.28 (0.09-0.90), 0.30 (0.11-0.88) and 0.32 (0.10-0.98), respectively. CONCLUSION: Single-dose combination of metronidazole and gentamicin seems sufficient to reduce SSIs in uncomplicated appendicitis patients despite whether the antibiotic was administered preoperatively or intraoperatively.

Adolescent↗

Antibiotic prophylaxis of infective endocarditis during digestive endoscopy: over- and underuse in Switzerland despite professed adherence to guidelines.

BACKGROUND AND STUDY AIMS: Guidelines for antibiotic prophylaxis of infective endocarditis associated with gastrointestinal endoscopy are not uniform. Though based on weak scientific evidence, they do represent an attempt to unify the management of antibiotic prophylaxis. We investigated whether physicians who profess to adhere to these guidelines actually do apply them correctly. MATERIALS AND METHODS: A questionnaire was sent to all 195 Swiss gastroenterologists asking whether they adhered to antibiotic prophylaxis guidelines and under what conditions did they apply antibiotic prophylaxis in gastrointestinal endoscopy. We analysed whether the Swiss gastroenterologists who claim to adhere to these guidelines actually do so in practice. RESULTS: The response rate to our questionnaire was 95%. Of the Swiss gastroenterologists, 60% correctly employ antibiotic prophylaxis guidelines in gastroscopy, as do 47% in colonoscopy. In therapeutic endoscopy, the percentage of correct antibiotic prophylaxis use depends upon the type of intervention and varies between 21 and 58%. Overuse of antibiotic prophylaxis is at least twice as frequent in colonoscopy and therapeutic endoscopy than in gastroscopy. CONCLUSIONS: Guidelines for antibiotic prophylaxis are not well applied and do not lead to uniform management despite a high degree of professed adherence to them. This phenomenon can be explained by "cognitive dissonance" and "reactance." We conclude that guidelines based on unconvincing data may even prove harmful.

Antibiotic Prophylaxis↗

Prospective multicenter study of antibiotic prophylaxis in operative treatment of appendicitis.

BACKGROUND/AIMS: A prospective, multicenter observation study was conducted to investigate the effectiveness of antibiotic prophylaxis in the operative treatment of appendicitis. METHODS: Between June 1996 and May 1997, a total of 4,968 patients underwent an operation for appendicitis at 34 East German hospitals. 41.4% (n = 2,424) received perioperative antibiotic prophylaxis whereas in 58.9% of the cases this was not given. The patients who received antibiotic prophylaxis constituted a negative selection, both with regard to risk factors and to the stage of inflammation. RESULTS: In the total test group, the rate for septic disorders of wound healing amounted to 2.5% (n = 120). The use of antibiotic prophylaxis makes it possible to significant lower the incidence of postoperative septic disorders of wound healing (p < 0.001). In both conventional (0.7% with prophylaxis vs. 3.8% without) and in laparoscopic appendectomy (0 vs. 1.0%) the rate for septic disorders of wound healing can be reduced (p < 0.001). The global comparison irrespective of possible antibiotic prophylaxis shows a significant advantage for appendectomies which started with laparoscopy (p = 0.008), but in the subgroups with prophylaxis this advantage is completely neutralized (p = 0.78). CONCLUSION: From this one can deduce that conventional appendectomy with antibiotic prophylaxis comprises no higher risk of wound infection than laparoscopy, since the risk of conversion exists for every operation begun by laparoscopy. These results would lead to the conclusion that antibiotic prophylaxis should be given before every appendectomy, whether by laparoscopy or conventional methods.

Adolescent↗

[Our experience in introducing current antibiotic prophylaxis into abdominal surgery--the initial results].

Over a one-year period (Nov. 1996-Nov. 1997), a total of 154 patients are admitted on an emergency basis, with deferred emergency and for routine treatment in the Clinic of Emergency Surgery. They are distributed in three groups, as follows: patients not requiring perioperative antibiotic prophylaxis and postoperative antibiotic therapy--27, patients subjected to perioperative parenteral antibiotic prophylaxis under adequate hospital conditions--121, and patients undergoing antibiotic prophylaxis in conditions inappropriate for its application--six. The drug schemes elaborated are in conformity with worldwide and Bulgarian experience along this line, and with the concrete hospital and economical conditions in this country. In all patient indicated for antibiotic prophylaxis the listed below antibacterial agents (presented as drug schemes) are administered i.v. a single time prior to anesthesia induction: in operations on the gastrointestinal tract except for interventions in acute appendicitis: cephalotin/cefazolin 2.0 g and metronidazole 0.5 g i.v.; in operations for acute appendicitis: amoxicillin/clavulanate 1.2 g and petronidazole 0.5 f i.v.; biliary surgery free of extrahepatic cholestasis: cephalotin/cefazolin 2.0 g i.v.; biliary surgery with present or preceding extrahepatic cholestasis: cefotetan 2 g i.v.; contaminated liver cysts (parasitic and nonparasitic): cefotetan 2 g i.v.; abdominal trauma without perforation of a hollow organ: cefotetan 2 g i.v.; in plastic repair of the anterior abdominal wall (congenital defects, postoperative eventration) and in poor risk patients (local and general status: cephalotin/cefazolin 2.0 g i.v. In 135 patients the postoperative period runs a course free of complications worthy of notice. Complications directly linked to introduction of the method proposed are recorded in ten cases: operative wound suppuration (4) and hospital infection (6). Complications not related directly to the procedure are observed in nine cases: urinary tract infection (4), bronchopneumonia (2), fever with unknown source of infection (including negative hemoculture) necessitating additional antibiotic therapy (2) and secondary infection (within a week of intervention) necessitating further therapy with antibiotics. The specific features of antibiotic prophylaxis used in the various types of operative interventions are discussed from microbiological, clinical and pharmacotherapeutic viewpoints. The obtained results are compared with pertinent literature data on the issue with a special reference to the clinical efficacy attained. They mirror the approach against the background of the concrete hospital conditions in this country. The method developed is fully consistent with the level of surgical expertise in Bulgaria. All efforts should be aimed at intrahospital environment improvement by means of meticulous asepsis and antisepsis.

Abdomen↗

Antibiotic prophylaxis in unrepaired CSF fistulae.

The value of antibiotic prophylaxis in patients with Cerebrospinal Fluid Leakage (CSF) is debatable. The aim of this study was to determine the value of prophylactic antibiotics in these patients. The study population comprised 253 patients with definite CSF leaks, of whom 106 received adequate antibiotic prophylaxis (Group A) and 109 were not treated with antibiotics (Group B). Thirty-eight patients were excluded from the analysis because they received antibiotics for reasons other than the CSF leakage. The two groups were closely matched for age, sex, type of CSF fistula, site, and duration of CSF leakage and presence or absence of skull fractures, but there were more patients with facial fractures and pneumocephalus in those who were treated with antibiotics. The first week meningitis rate was 6.6 and 9.17% in the treated and untreated groups, respectively, while the annual risk of meningitis was 7.6% in the treated and 11.9% in the untreated group. However, these differences did not reach significance (P > 0.05). The survival curves of meningitis-free survival were similar in the two groups, particularly during the first 4 weeks during which antibiotics were given (Log Rank test, p > 0.05). Furthermore, there were more cases of Gram-negative infection and of partially-treated meningitis in the treated group. Although this was a retrospective, non-randomized study, it confirms the conclusions of previous smaller series, that prophylactic antibiotics do not significantly reduce the risk of meningitis in these patients. It is ethically justifiable to withhold antibiotic prophylaxis in patients with CSF fistulae until a prospective controlled double blind trial has settled the question.

Adult↗

Single-dose antibiotic prophylaxis in patients at high risk for infection in biliary surgery: a prospective and randomized study comparing cefonicid with mezlocillin.

The usefulness of antibiotic prophylaxis in biliary surgery is well established. When antibiotic prophylaxis is not used, wound infection rates after biliary surgery range from 10% to 25%. With antibiotic prophylaxis, the rates can be reduced to less than 5%. Three questions are still controversial: Do all patients undergoing biliary surgery require antibiotic prophylaxis? What is the ideal antibiotic for use in biliary surgery? What should be the duration of antibiotic prophylaxis? In this study we prospectively evaluated the efficacy of a single dose of antibiotic prophylaxis in biliary surgery, administered to patients at high risk for infection, in a trial comparing cefonicid (a cephalosporin with a long half-life) with mezlocillin (a broad-spectrum ureidopenicillin).

Adult↗

Antibiotic prophylaxis for full-face laser resurfacing: is it necessary?

OBJECTIVE: To evaluate the need for antibiotic prophylaxis when performing full-face laser resurfacing. METHOD: Prospective study of 31 patients undergoing full-face laser resurfacing, 17 with and 14 without antibiotic prophylaxis. OBSERVATION: Four of 14 patients without antibiotic prophylaxis had microbiologic and clinical evidence of infection. None of the 17 patients with antibiotic prophylaxis had clinical infection. Early treatment prevented adverse sequelae in the 4 patients who developed infection. CONCLUSION: Antibiotic prophylaxis against Staphylococcus aureus is useful but not essential, because meticulous wound care and close clinical monitoring of patients daily with routine bacterial swabs can detect infection early.

Antibiotic Prophylaxis↗

[Antibiotic prophylaxis and hernia repair. Systematic quantitative review results].

BACKGROUND: The usefulness of the antibiotic prophylaxis in hernia repair is currently a controversial subject. Comparative studies have shown disparate results, and that is why it is difficult to have a clear idea of its utility. The purpose of the present study is to make a systematic quantitative review or meta-analysis of the published controlled studies on antibiotic prophylaxis in hernia repair, to give the best possible evidence as to the effectiveness of this prophylaxis. METHODS: The described steps for the realization of a systematic quantitative review, based on the practice of evidence based medicine, have been followed. The steps are these: formulation of a relevant question (is antibiotic prophylaxis useful in open inguinal hernia repair in the prevention of post-operative infection of surgical wound?), search of the best available evidence, selection criteria of those trials found, analysis of each one of them, combination of the results (Yusuf and Peto method) and conclusions.Results. Twelve studies were found, of which eight fulfilled the inclusion criteria for the meta-analysis. Our results show that antibiotic prophylaxis in hernia repair, whether prosthetic material is used or not, diminishes the rate of infection by 42%, 61% and 48% in herniorraphies, hernioplasties and the two combined, respectively. The number of patients to whom prophylaxis was administered in order to avoid a post-operative infection was 42 for herniorraphies, 37 for hernioplasties and 40 for general hernia repair.Conclusions. Antibiotic prophylaxis in hernia repair is useful in preventing wound infection. Nevertheless, this does not imply its indiscriminate administration, rather it is necessary to base it on the local rate of wound infection and on the analysis of the patients' risk factors in order to avoid its administration when the possible benefit is considered to be limited.

Antibiotic Prophylaxis↗

Prospective randomized trial of antibiotic prophylaxis in acute leukemia.

Patients undergoing initial remission induction chemotherapy for acute leukemia in a protected environment unit were randomly assigned to parenteral antibiotic prophylaxis or oral and parenteral antibiotic prophylaxis. Complete remissions were obtained in 82 percent of the 45 patients receiving oral and parenteral antibiotic prophylaxis and 76 percent of the 41 patients receiving parenteral antibiotic prophylaxis. Approximately 20 percent of the patients in both groups have had a continuous complete remission for more than five years. The episodes of fever of unknown origin and major infection were significantly more common in patients receiving parenteral antibiotic prophylaxis, although the episodes of local infection were similar in both groups. The duration of remission and survival was similar in both groups. Hence, the oral and parenteral antibiotic regimen was more effective for infection prophylaxis, but had no effect on response to antileukemic chemotherapy.

Acute Disease↗

Antibiotic prophylaxis for cerebrospinal fluid shunts: a metanalysis.

The value of antibiotic prophylaxis for clean neurosurgical procedures without the implantation of a foreign body has been conclusively demonstrated. Attempts to confirm its efficacy for cerebrospinal fluid shunt operations have produced confusing and inconclusive results. The objective of this study was to combine the results of high-quality controlled trials of antibiotic prophylaxis for cerebrospinal fluid shunt operations and to determine if there is evidence for the efficacy of this policy. Randomized clinical trials identified from presentations at national meetings and in the published literature were subjected to a metanalysis. The pooled data suggest a statistically significant effect favoring antibiotic prophylaxis (approximately a 50% reduction in infection risk when antibiotic prophylaxis is used). The effect is strongly related to the baseline infection rate when prophylaxis is not used and disappears when the baseline infection rate is at or below about 5%.

Adolescent↗