The opinion of the Court was delivered by
Sullivan, J.Plaintiff, the holder of, and named beneficiary in, a Major Medical Expense Policy issued by defendant, filed suit seeking reimbursement for medical expenses incurred on behalf of his son Matthew, a child born while the policy was in force. Involved were the medical costs of treating Matthew for a condition of cystic fibrosis.
Defendant denied liability. It admitted that its policy insured plaintiff and the covered members of his family against loss resulting from sickness which was defined in the policy as “sickness or disease contracted and commencing after the effective date of this Policy as to the person whose sickness is the basis of claim.” It also admitted that under the terms *558of the policy a child bom to the named insured automatically became a “Covered Member,” but only “upon attaining the age of fifteen days.” Its contention was that Matthew’s cystic fibrosis had been contracted and had commenced at birth or within a few days thereafter, which was prior to the effective date of the policy as to him.
At trial, defendant moved to dismiss plaintiff’s case on the ground that coverage did not exist as a matter of law. However, the trial court ruled that a factual issue existed as to when the cystic fibrosis had commenced. The ease was submitted to the jury which returned a verdict for plaintiff. Judgment was entered in favor of plaintiff for $3,241.91, the amount of medical expenses to date, with the further provision that plaintiff would be entitled to payment of future medical expenses incurred by reason of Matthew’s condition of cystic fibrosis up to the maximum policy limit of $12,500.
On appeal the Appellate Division reversed in an unreported opinion, holding that no factual issue was involved since, on the proofs, reasonable minds could not differ as to the disease having commenced and become manifest within the first fifteen days of the infant’s life. It held that defendant’s motion to dismiss should have been granted. This Court granted certification. 64 N. J. 313 (1973).
Cystic fibrosis is an inherited disease present at birth, although indications of it may not appear immediately. The disease cannot be cured. The only treatment for it is supportive. Its symptoms include lung insufficiency, instability of the pancreatic glands and thick mucous secretions which tend to block various organs of the body.
In the instant case, Matthew was born on June 1, 1969 with a mucous blockage of his intestinal tract which required immediate surgery. His condition was diagnosed as meconium ileus. The condition results from enzyme, mucous'gland and pancreatic malfunctions. All of the experts agreed that some degree of correlation exists between meconium ileus and cystic fibrosis. There was testimony *559that 10% of all cystic children are born with meconium ileus. Conversely, most, if not all, meconium ileus children develop cystic fibrosis. Defendant’s medical expert, Dr. Maraño, said that meconium ileus is conclusively pathognomonic (indicative or characteristic) of cystic fibrosis. However, plaintiff’s expert, Dr. Schiffman, testified that not all infants born with a condition of meconium ileus become cystic.
In the present case there was an immediate diagnosis of meconium ileus, and surgery had to be performed to reliéve the condition. There was also a strong suspicion that the baby had cystic -fibrosis and a presumptive diagnosis thereof was made. Enzyme treatment for this condition was attempted but was discontinued after a few days because of an adverse reaction. On June 27 a sweat test was administered to confirm the presumptive diagnosis of cystic fibrosis, but results were inconclusive since the child did not sweat enough.1 He was discharged from the hospital on July 1, 1969 with a diagnosis of “cystic fibrosis — meconium ileus — pneumonia.”
In August 1969, Matthew was brought to the Cystic Eibrosis Clinic at Hackensack Hospital and on August 22 another sweat test was administered, this time with positive results. All of the experts agreed that the August 22 test established that Matthew had cystic fibrosis.
At the present time his eystice fibrosis affects his upper respiratory system. He has a constant runny rose, has difficulty breathing and is required to sleep in a mist tent and take enzymes and other drugs. The record does not indicate when this upper respiratory problem manifested itself, although the July 1, 1969 hospital discharge lists “pneumonia” as part of the diagnosis.
Under the policy, Matthew became a “Covered Member” fifteen days after his birth. The issue is whether his cystic *560fibrosis was a disease “contracted and commencing” after the policy became effective as to him.
The Appellate Division held that the disease in fact manifested itself sufficiently in the first fifteen days of the infant’s life so that it could be said without doubt to have then commenced, thereby excluding coverage.
We do not agree that the proofs are that clear. Dr. Sank, who was the attending pediatrician, and who was called as a witness by defendant, testified that his working diagnosis of the infant’s condition was meconium ileus. He stated that it was very difficult to say when the cystic fibrosis “commenced,” but that there was a presumed diagnosis thereof made at about one or two weeks of age. However, the hospital report covering Matthew’s one-month stay makes no mention of cystic fibrosis until near the discharge date.
Dr. Maraño, defendant’s other medical expert, testified that cystic fibrosis while congenital, and, therefore, present at birth, may not manifest symptoms “until years after birth or may not be recognized until later.” However, he said that in Matthew’s case the diagnosis of meconium ileus confirmed on the third day of his life, was pathognomonic of cystic fibrosis and amounted to a diagnosis of that disease at that time.
Plaintiff’s medical expert was Dr. Schiffman, a pediatrician and specialist in cystic fibrosis, who has had Matthew under treatment since August 1969. He agreed that Matthew has cystic fibrosis and that it was present at birth. However, his opinion was that the disease was not definitely diagnosed until August 22, 1969, when a sweat test was administered with positive results. He said that meconium ileus may not be related to cystic fibrosis although most likely a treating physician finding a condition of meconium ileus would suspect cystic fibrosis. However, he said “there are cases of children with intestinal obstruction, meconium ileus, who are not cystics — who do not have cystic fibrosis.” In support of this opinion he referred to a seven-year old patient of his who had meconium ileus at birth, but has had *561no symptoms of cystic fibrosis. He noted that the hospital record showed that Matthew was not discharged from the hospital on enzymes (a supportive treatment for cystic fibrosis).
The fact that all medical experts are in agreement that Matthew has cystic fibrosis and that it was present at birth is not dispositive of the ease. Defendant admits that symptoms of cystic fibrosis may not appear for years and that in the present case, if the disease did not manifest itself within the first fifteen days of the infant’s life, coverage would exist.
The record indicates that while cystic fibrosis is a generalized disease, the symptomotology is variable. Inter alia, it may appear as an intestinal condition, an upper respiratory condition or a liver condition. The problem is to recognize the particular condition as a certain manifestation of cystic fibrosis. Dr. Sank and Dr. Maraño both testified that Matthew’s meconium ileus was a symptom or characteristic sign of cystic fibrosis. Dr. Schiffman, on the other hand, disagreed and said that there are cases of children with meconium ileus who are not cystics, i. e., that meconium ileus may or may not be indicative of cystic fibrosis.
The policy should be read as the ordinary policyholder would understand it. We take the words “contracted and commencing” to mean that coverage would exist where the first positive symptoms of the disease did not manifest themselves with reasonable certainty within the first fifteen days of Matthew’s life.
In the light of all of the testimony and the varying inferences that could be drawn therefrom, . the issue of whether Matthew’s cystic fibrosis commenced within the fifteen-day period during which coverage did not exist as to him, was properly left to the jury. Accordingly, the judgment of the Appellate Division is reversed and the judgment of the trial court in favor of plaintiff is hereby reinstated.
sweat test, a reliable indicator of cystic fibrosis, measures the body’s sodium chloride level. Cystic fibrosis children have a high level of sodium chloride.