Opinion by
Mr. Justice Williams,.- The plaintiff seeks to compel by a writ of mandamus the admission of his minor son to the common school of the city of Williamsport. The board of school directors admits that the child is of proper age, is in good health, and possesses the qualifications that are enumerated in the general school laws as those that entitle him to admission. They allege however that he is excluded because of non-compliance with a regulation adopted in the exercise of a proper measure of care for the public health. The facts appearing in the answer are substantially as follows:
First. That the city of Williamsport provided by an ordinance adopted in 1872 and still in full force that'no pupil “shall be permitted to attend any public or private school in said city without a certificate of a practicing physician that such pupil has been subjected to the process of vaccination.” Second. That smallpox now exists in Williamsport and “is and has been epidemic in many near by cities and towns.” Third. That in view of this situation the attention of the school board was drawn to the subject by a communication from the board of health requesting them to take action “ to the effect that no pupil shall attend the schools of this city except they be vaccinated or furnish a certificate from a physician that such vaccination has been performed.” Fourth. That upon considering this communication “ and from the gen*483eral alarm prevailing in the city over the report that a case of smallpox was in the city ” they adopted a resolution in conformity with the recommendation of the board • of health. Fifth. That this resolution is not enforced against those not at present in a condition to undergo vaccination; and as to those unable to bear the expense, the board provide vaccination without charge.
The plaintiff demurred to this answer, and the questions thus raised are over the power of the school board to adopt reasonable health regulations for the benefit of their pupils and the general public, and over the reasonableness of the particular regulation complained of in this case. It should be borne in mind that there is no effort to compel vaccination. The school board do not claim that they can compel the plaintiff to vaccinate his son. They claim only the right to exclude from the schools those who do not comply with such regulations of the city and the board of directors as have been thought necessary to preserve the public health. It would not be doubted that the directors would have the right to close the schools temporarily during the prevalence of any serious disease of an infectious or contagious character. This would be a refusal of admission to all the children of the district. They might limit the exclusion to children from infected neighborhoods, or families in which one or more of the members was suffering from the disease. For the same reason they may exclude such children as decline to comply with requirements looking to prevention of the spread of contagion, provided these requirements are not positively unreasonable in their character.
Is the regulation now under consideration a reasonable one ? That is to be judged of in the fiist instance by the city authorities and the school board. It is only'in the case of an abuse of discretionary powers that the court will undertake to supervise official discretion. Vaccination may be, or may not be, a preventive of smallpox. That is a 'question about which medieal men differ and which the law affords no means of determining in a summary manner. A decided majority of the medical profession believe in its efficacy. The municipal regu-' lations of many, and I have no doubt of most, of the cities of this state and country, provide for it. In the present state of medical knowledge and public opinion upon this subject it *484would be impossible for a court to deny that there is reason for believing in the importance of vaccination as a means of protection from the scourge of smallpox. The question is not one of science in a case like the present. We are not required to determine judicially whether the public belief in the efficacy of vaccination is absolutely right or not. We are to consider-what is reasonable in view of the present state of medical knowledge and the concurring opinions of the various boards and officers charged with the care of the public health. The answers of the city and the school board show the belief of the proper authorities to be that a proper regard for the public health and for the children in the public schools, requires the adoption of the regulation complained of. They are doing, in the utmost good faith, what they believe it is their duty to do; and though the plaintiff might be able to demonstrate by the highest scientific tests that they are mistaken in this respect,, that would not be enough. It is not an error in judgment, or-a mistake'upon some abstruse question of medical science, but an abuse of discretionary power, that justifies the courts in interfering with the conduct of the school board or setting aside its action. It is conceded that the board might rightfully exclude the plaintiff’s son if he was actually sick with, or was just recovering from, the smallpox. Though he might not be affected by it, yet if another member of the same family was, the right to exclude him, notwithstanding he might be in perfect health, would be conceded. How far shall this right, to exclude one for the good of many be carried ? That is a question addressed to the official discretion of the proper officers; and when that discretion is honestly and impartially exercised the courts will not interfere.
The learned judge of the court below reached a correct conclusion in this case, and his decree is now affirmed at the cost of the appellant.